-3x = 3 + y
3 + y - 5y = -21
-4y = -24
y = 6
x = -3
That's exactly the purpose of the substitution method ... to get an equation with one less variable. When you have it, you solve it for the variable that's left.
Substitution method: from first equation y = 5x - 8. In the second equation this gives 25x - 5(5x - 8) = 32 ie 25x - 25x + 40 = 32 ie 40 = 32 which is not possible, so the system has no solution. Multiplication method: first equation times 5 gives 25x - 5y = 40, but second equation gives 32 as the value of the identical expression. No solution.
y= -4x-7 y=3x 3x= -4x-7 3x+4x=7 7x=7 x=1
From Equation 1: x = 3y - 23Substitute for x in equation 2: 5(3y - 23) + 6y = 74ie 15y - 115 + 6y = 74ie 21y - 115 = 74Add 115 to each side: 21y = 189Divide each side by 21: y = 9x = 3y - 23 ie 27 - 23 ie 4x = 4, y = 9
3x+y = 10 y = x-2 Substitute the value of y into the top equation: 3x+x-2 = 10 => 4x = 10+2 => 4x = 12 => x = 3 Substitute the value of x into the original equations to find the value of y: So: x = 3 and y = 1
by elimination,substitution or through the matrix method.
x+y=5
how do you use the substitution method for this problem 2x-3y=-2 4x+y=24
-2
That's exactly the purpose of the substitution method ... to get an equation with one less variable. When you have it, you solve it for the variable that's left.
2x-3y=13
This is not Calculus.y=7(Already solved)substiute y=7 into y=8xtherefore 7 = 8xtherefore x = 7/8
There are no disadvantages. There are three main ways to solve linear equations which are: substitution, graphing, and elimination. The method that is most appropriate can be found by looking at the equation.
Substitution method: from first equation y = 5x - 8. In the second equation this gives 25x - 5(5x - 8) = 32 ie 25x - 25x + 40 = 32 ie 40 = 32 which is not possible, so the system has no solution. Multiplication method: first equation times 5 gives 25x - 5y = 40, but second equation gives 32 as the value of the identical expression. No solution.
From first equation: y = 2x - 5Substitute this in second equation: 3(2x - 5) - x = 5, ie 6x - 15 - x = 5ie 5x = 5 + 15 so x = 4 and y = 3
G-Given U-Unknown E-Equation S-Substitution S-Solve
The substitution method undoes the chain rule.