Question

5x+9y=−10
7x+10y=−1

help how do i solve this​

Answer 1

{x,y} = {7,-5}

Explanation:

Solve equation [2] for the variable y

[2] 10y = -7x - 1

[2] y = -7x/10 - 1/10

Plug this in for variable y in equation [1]

[1] 5x + 9•(-7x/10-1/10) = -10

[1] -13x/10 = -91/10

[1] -13x = -91

Solve equation [1] for the variable x

[1] 13x = 91

[1] x = 7

By now we know this much :

x = 7

y = -7x/10-1/10

Use the x value to solve for y

y = -(7/10)(7)-1/10 = -5

Answer 2

(x , y) = (7 , -5)

Explanation:

{x, y} = {7, -5}

System of Linear Equations entered :

1. 5x + 9y = -10

2. 7x + 10y = -1

(Shown on graph below)

Solve equation 3 for the variable the y

10y = -7x - 1

y = -7x/10 - 1/10

Plug this in for variable y in equation 1

5x + 9•(-7x/10-1/10) = -10

-13x/10 = -91/10

-13x = -91

Solve equation 1 for the variable x
13x = 91

x = 7

By now we know this much :

x = 7

y = -7x/10-1/10

Use the x value to solve for y

y = -(7/10)(7)-1/10 = -5

Hence, (x , y) = (7 , -5)