By Simultaneous Equations. Assuming you mean
5x + 3y + 20 = 0
2x - y - 14 = 0.
We will eliminate 'y' by multiplying the bottom eq'n by '3' and then adding.
Hence
5x + 3y + 20 = 0
6x - 3y -42 = 0
Add
11x -22 = 0
11x = 22
x = 22/11
x = 2
when x= 2
2(2) - y - 14 =0
4 - y - 14 = 0
-y - 10 = 0
y = -10
So the point of intersection in ( x.y.) form is ( 2, -10).
Chat with our AI personalities
I presume that you mean 5x + 3y + 20 = 0 and 2x - y - 14 = 0.
First put the formulae in the form y = mx + c.
3y = -5x -20
y = -5/3 x -20/3
and
y = -2x + 14
Substitute the second formula into the first
-2x - 14 = -5/3 x -20/3
-6x - 42 = -5x - 20
-42 = x - 20
x = -22
Substitute into equation
y = -2x + 14
y = -2 x -22 + 14
y = 44 + 14
y = 58
Therefore the two lines meet at point (-22, 58).
- 2x - 14 = 26 Switch all signs: 2x + 14 = - 26 Subtract 14 from both sides: 2x = -26 - 14 = - 40 Divide both sides by 2: x = - 40/2 = - 20
You need to be more clear about your question. 3x + 6y = 18 2x + 5y = 20 The two equations you give represent lines. I assume you're trying to find the point at which they intersect. There are various ways to work this out. One technique is to multiply each equation by a factor that gives one of the two variables the same coefficient. For example, if we multiply the first equation by 2, and the second equation by 3, we get: 6x + 12y = 36 6x + 15y = 60 Then we can subtract one from the other, which gives us a solution for y: [6x + 12y = 36] - [6x + 15y = 60] _______________ [0x - 3y = -24] So -3y = -24, telling us that at the point of intersection, y = 8. We can then plug that back into one of the original equations and solve for x: 2x + 5y = 20 2x + 5(8) = 20 2x = 20 - 40 2x = -20 x = -10 So the lines intersect at the point (-10, 8). Another way to work it out is to solve one of the equations for a single variable, and then plug it into the other one: 3x + 6y = 18 ∴ x + 2y = 6 ∴ x = 6 - 2y 2x + 5y = 20 ∴ 2(6 - 2y) + 5y = 20 ∴ 12 - 4y + 5y = 20 ∴ y = 20 - 12 ∴ y = 8 That gives us the value 8 for y, which we can once again plug in to either of the original equations to find x: 2x + 5y = 20 ∴ 2x + 40 = 20 ∴ 2x = -20 ∴ x = -10 Once again telling us that the lines intersect at the point (-10, 8)
As stated these are not lines, but just a collection of algebraic terms. If we change them to y=2x and y=2x-1, then on a graph of y versus x, these are parallel lines separated by vertical distance of 1.
2x - 5 = 15 2x = 20 x = 10
2x+4 = -16 2x = -16-4 2x = -20 x = -10