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Solve the system using substitution: y + 8x = 10 and 2y - 4x = 40

PLS HURRY I NEED THIS DONE IN 10 MINS. HELP ME ASAP PLEASE

User Juuro
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1 Answer

14 votes

Answer:

Hence x = -1 and y = 18

Explanation:

Given the system of equations

y + 8x = 10... 1

2y - 4x = 40 ... 2

From 1; y = 10-8x

Substitute into 2;

2(10-8x) - 4x = 40

20 - 16x - 4x = 40

20 - 20x = 40

-20x = 40 - 20

-20x = 20

x = -1

Recall that y = 10-8x

y = 10 - 8(-1)

y = 10 + 8

y = 18

Hence x = -1 and y = 18

User Jabalsad
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