Question

Heather has to solve this system of equations using elimination. what should be her first step?

a. isolate the x in the second equation so that she can substitute into the first equation

b. solve both equations for y so that she can easily graph the equations and find the point of intersection

c. multiply the second equatuon by 3 so that the x's have the same coefficient to then add the two equations together

d. multiply the second equation by -3 so that the x's have the opposite coefficients to then add the two equations together

Answer 1

The answer is D) multiply the second equation by -3 so that the x's have the opposite coefficients to then add the two equations together

TRUST ME!

I took USATestPrep and I got it wrong by choosing answer choice A from

Laurenercsp6fpli answer!

Answer 2

(D) multiply the second equation by -3 so that the x's have the opposite coefficients to then add the two equations together

Explanation:

The given system of equations are:

`3x+6y=12` (1)

and
`x+5y=10` (2)

Upon solving the given system of equations, multiply the second equation by -3 so that the x's have the opposite coefficients to then add the two equations together such that

`3x+6y=12`

`-3x-15y=-30`

Adding the above equations, we get

`-9y=-18`

⇒
`y=2`

Substituting the value of y=2 in equation (1), we have

⇒
`3x+6(2)=12`

⇒
`3x+12=12`

⇒
`3x=0`

⇒
`x=0`

Hence, option D is correct.