Answered

54:19 To eliminate the terms and solve for y in the fewest steps, by which constants should the equations be multiplied by before adding the equations together? First equation: 9x + 3y = -18 Second equation: 8x + 7y = 10 The first equation should be multiplied by 3 and the second equation by 7. The first equation should be multiplied by -3 and the second equation by -7. The first equation should be multiplied by - 7 and the second equation by 3 . The first equation should be multiplied by -7 and the second equation by -3.

Answer :

MRROYALGO

Answer:

The first equation should be multiplied by - 7 and the second equation by 3

Step-by-step explanation:

Given

[tex]9x + 3y = -18[/tex] -- (1)

[tex]8x + 7y = 10[/tex] -- (2)

Required

How to eliminate y

In (1), the coefficient of y = 3

In (2), the coefficient of y = 7

Multiply the first equation by -7

[tex]-7(9x + 3y = -18)[/tex]

[tex]-63x -21y = 126[/tex] --- (3)

Multiply the second by 3

[tex]3(8x + 7y = 10)[/tex]

[tex]24x + 21y = 30[/tex] -- (4)

Add the results together:

[tex]-63x -21y = 126[/tex]

[tex]24x + 21y = 30[/tex]

[tex]-------------------------[/tex]

[tex]-63x + 24x -21y +21y = 126+30[/tex]

[tex]-63x + 24x = 126+30[/tex]

See that y is eliminated

Go Question: Other Questions