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Solve this system of linear equations. Separate

the x- and y-values with a comma.
9x = 1 - 4y
-7x = -7 + 4y

User GrandMagus
by
5.5k points

1 Answer

6 votes

Answer:

y = 7 and x =3

Explanation:

use elimination method

so we gonna eliminate y first

9x = 1 - 4y

-7x = -7 + 4y

7| 9x = 1 - 4y

9| -7x = -7 + 4y

63x = 7 - 28y

-63x = -63 + 36y

add eqtn 1 to eqtn2

you will get

0 = -56 + 8y

56 = -56 + 56 + 8y

56 = 8y

56÷8 = 8y÷ 8

7 = y

also eliminate x as we have done wth y

4| 9x = 1 - 4y

4| -7x = -7 + 4y

36x = 4 - 16y

-28x = -28 + 16y

add the two equations

u will get

8x = -24 + 0

8x = -24

8x÷8 = 24÷ 8

x = 3

User Konrad Krakowiak
by
6.0k points