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2 years ago

I need help substituting number 4.

Mathematics

2 answers:

Aleksandr [31]2 years ago

7 0

Solve, for the first variable in one of the equation, the substitute the final result into the other equation

- $\frac{17}{3}$ ; - $-\frac{211}{21}$

Butoxors [25]2 years ago

3 0

I solved for x first by substituting y into equation # 2.

-4y - 30 = -6x = -4y = -6x+30 = y = (6x-30)/4

25 = -7y + 8x

25 = -7(6x-30)/4 + 8x

25 = (-42x + 210)/4 + 8x

25 = -10.5x + 52.5 + 8x

-27.5 = -2.5x

x = 11

Now solve for y

-4y - 30 = -6x

-4y - 30 = -66

-4y = -36

y = 9

Plug both numbers into the equations above and your answer checks out.

-4(9) - 30 = -6(11)

-36 - 30 = -66 (True)

25 = -7y + 8x

25 = -7(9) + 8(11)

25 = -63 + 88 (True)

hope this helps unless I totally misunderstood what the question was (which happens)

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