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Use the substitution method to solve the system of equations Choose the correct ordered pair 2x plus 3y equals 13 x equals 2?
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∙ 9y ago
(2,3)
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∙ 9y ago
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Is (1 10) a solution to this system of equations?
No because there are no equations there to choose from.
Choose the correct expression that has 3 as an exponent z as a base and 8 as a coefficient?
8z^3
How do you solve systems of linear equations?
When given multiple linear equations and asked to solve for certain variables, the first requirement is that you have as many equations as you have variables. If you have more equations than variables, that's fine; just use whichever are the simplest. If you have more variables than equations, the best you can do is solve for one variable in terms of another. In a scholastic setting, you would normally have the same number of variables as equations. That is what will be assumed for the remainder of this article. The most common format of a system of linear equations is this: y=2x+3 y=x+5 When asked to solve these equations, what's really being asked is for you to find where those two lines intersect. This allows you to assume that the x value and y value will be the same at that point. Therefore, you can say that y=2x+3=x+5 2x+3=x+5 x=2 Then, since we know that x=2, we can put that value into either of the initial equations to solve for y. Let's choose the second one, because then we don't have to worry about multiplying by two. y=x+5 y=2+5 y=7 Therefore, the two lines intersect at the coordinates (2,7). This method is normally referred to as solving by comparison, which is a special case of solving by substitution (see below). Sometimes, equations are not formatted in a way that solving by comparison is convenient. For example, perhaps something like this is given: 6=9y-3x 2y=3x+4 In situations like these, it is often necessary to do some algebra before combining the equations in some way. Let's try to isolate the variable x in the first equation. 6=9y-3x 3x+6=9y 3x=9y-6 x=3y-2 Now that we have x in terms of y, let's put that new equation into the second given equation. 2y=3(3y-2)+4 2y=9y-6+4 2y=9y-2 2=7y y=2/7 Again, putting this y value into the first equation, we get: 6=9y-3x 6=9(2/7)-3x 6=18/7-3x 6-18/7=3x 42/7-18/7=3x (in this step, we multiplied 6 by 7/7) 24/7=3x 24/7*(1/3)=x x=24/21 Therefore the coordinates that these two lines intersect at is (24/21,2/7). You'll notice that this set of coordinates are less appealing than the integers found in the first problem. Since substitution is a very general method of solving linear equations, it will work under any circumstances. If you have doubts about using comparison (or the final method, outlined below) then use substitution. Provided you don't make any mistakes in the mechanics, substitution will get you the correct answer. The final method is called elimination. Using this method, one can often avoid long and tedious algebra. For example: 2x+y=1 -2x+2y=5 If we were to use substitution, we would get the correct answer (though we'd have to isolate a variable, expand a bracket, isolate for the other variable in terms of the first, substitute that equation into the other, and eventually solve for both variables). However, there is an easier way. We can add the two equations together. 2x+(-2x)+y+2y=1+5 0+3y=6 y=2 Substituting y=2 into the first equation, we get: 2x+y=1 2x+2=1 2x=-1 x=-(1/2) Therefore the coordinates that these two lines intersect at is (-1/2,2) It is worth noting that we are not limited to adding the two equations together. We may also subtract, multiply, and divide the equations. Elimination often takes the most practice to spot when it will be useful, but it can save many lines of math when applied in a suitable manner (as in the last example). Those are the basic methods for solving two equation, two unknown problems. They will also hold true for three or more equation/unknown problems, but the mechanics of the solution becomes very long, very quickly. In more than two equation/variable questions, it is recommended to use matrices, but that is beyond the scope of this answer.
How do they solve two-solve equation?
I guess you mean simultaneous equations. There are three methods of solving these equations: graphing if the variables are x and y (though this is only an approximate method and should be avoided unless used to verify your answers, or if it's specified by the teacher), substitution (which should be used if one of the equations has one of the variables with a coefficient of 1), or the addition method (also known as elimination, as you try to eliminate one of the variables in order to find the value of the other). Since I can't demonstrate the graphing method, I'll write out the other two using the equations: 2x - 5y = 1 3x + 5y = 14 SUBSTITUTION: Here, you seek to substitute an alternate value of x or y into the equation from which you DID NOT extract the alternate value. Sounds complicated because I'm not very good at explaining. But I'll show it instead: I want to eliminate that 2 that is in front of the x in the first equation, so that I can find what x equals to in terms of y, and then substitute that value into the second equation. 2x - 5y = 1, I'll divide the entire equation by 2: x - 5y/2 = 1/2. I'll then rearrange the equation: x = 1/2 + 5y/2, yay! Now we sub it into equation 2; replace the value of x with the value we got here. 3x + 5y = 14 3(1/2 + 5y/2) + 5y = 14, expand the brackets... 3/2 + 15y/2 + 5y = 14, multiply the entire equation by 2 to cancel out the denominator: 3 + 15y + 10y = 28, and collect the like terms: 25y = 25. Therefore: y = 1 But we're not done yet! Now we have to sub this value of y into one of the equations, to find out what x is. Let's choose equation 1: 2x - 5y = 1 2x - 5 = 1 2x = 6 x = 3 And now we have our two answers: x = 3, y = 1. ELIMINATION: For this particular equation, elimination is a much more sensible method. I want to make the coefficients of one of the variables equal in both equations, so that I can add the two equations together (or subtract one from the other) and eliminate that set of variables. In the equations I've provided, hell yeah! The coefficients of y are already equal. Or well, almost. One is +5 and the other is -5, meaning that I can add the two equations together to cancel out y. (Because -5+5=0, of course.) (2x - 5y = 1) + (3x + 5y = 14), add all the like terms together to get: 2x + 3x = 1 + 14 5x = 15, x = 3. Now I know this is correct because of the substitution method I did before. Sub this value of x into one of the two equations like in the previous method, to get y = 1. GRAPHING: I'll just quickly summarise this; graphing can only be used if the two variables are x and y, because those are the only two variables in the equations of lines on a linear plane. So if you have a question with a, b, c, d and so on, just forget about this method entirely. Otherwise, you can use this method to graph the two lines, and any points of intersections represent the values for x and y that solve both equations, in this case the two lines intersect at one point (3,1). Unless your graphing skills are incredibly accurate, this method isn't very good for finding the answers to simultaneous equations. But otherwise, you can use this method to check if your answers are correct. For example, if you got an answer like x=1 and y=-6 for these two equations, you can then check the graph and know that something is incredibly wrong! Hope this helps.
One of the numbers of an ordered pair that locate a point on a coordinate graph?
An ordered pair shows how much distance you go in the x-direction and the y-direction. It is represented like this (x,y) You can assigned any number you want. (-2,5) (1,-3) (4,5) (-9,11) So to answer your question you can choose any number in the examples I gave you... therefore 1 can be your answer.
Use the substitution method to solve the system of equations Choose the correct ordered pair?
2x+7y=29 x=37-8y
Use the substitution method to solve the system of equations choose the correct ordered pairs x plus 2y 12 y x plus 3?
Without any equality signs they can't be considered to be equations. But if you mean: x+2y =12 and y = x+3 then the solution is as follows x+2y = 12 -x+y = 3 Adding the equations together: 3y = 15 and y = 5 By substitution: x = 2 Solution: x = 2 and y = 5
Use the substitution method to solve the system of equations. Choose the correct ordered pair. 2y plus 2x 20 y - 2x 4?
It is not possible to know exactly what the question is because the browser used by this site is almost totally useless for mathematical questions: it rejects most symbols. If the equations are 2y + 2x = 20 and y - 2x = 4,then the solution is (2, 8).
Is (1 10) a solution to this system of equations?
No because there are no equations there to choose from.
Choose the ordered pair that is a solution for this equation x - 3y -7?
10
Choose the ordered pair that is a solution to the system of equations -x plus y equals 12?
-x+y=12is the equation of a line and since there are infinitely many points on the line and each point is represented by an ordered pair, we have infinitely many solutions.If we take x as 0, then y must be 12so (0,12) is one ordered pair that is a solution to the equation.Zero is often a nice number to pick since it makes the calculation a bit easier.
How do you spell chooses?
That is the correct spelling of the verb "to choose" (the past tense is chose).
How do you choose an appropriate catalyst for a substitution reaction?
It depends upon the leaving group, that catalyst is suitable which has the attraction towards leaving group.
Is this the correct spelling for choose?
OK
How do you spell choose in present tense?
Choose is the correct spelling for the present tense.
Does the sperm choose what sex the baby is?
That is correct
what- choose the property of equality that justifies the step. prove: if z= 4+ x/6, y=2 and z= y, then x=-12?
substitution
