Question

Solve the system of equations.


−5x+2y=9
y=7x
​

Answer 1

`x=1\\y=7`

Explanation:

`-5x+2y=9\\y=7x`

Replace y in the first equation.

`-5x+2(7x)=9`

Distribute the 2 and combine like terms;

`-5x+14x=9\\9x=9`

Divide by 9

`x=(9)/(9)\\ x=1`

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After having found x, you can replace it in any of the equations to find y. I'll use the second equation.

`y=7x\\y=7(1)\\y=7`

Answer 2

x=1 y=7

Explanation:

−5x+2y=9

y=7x

Substitute the second equation into the first

-5x +2(7x) = 9

Distribute

-5x +14x = 9

Combine like terms

9x=9

Divide by 9

9x/9 =9/9

x= 1

Now find y

y = 7(1)

y = 7