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Question 9
10 pts
Solve this system of equations using substitution algebraically. Check your answer using
substitution.
3x + 4y = 36
y= x+8

User Don Tomato
by
5.0k points

1 Answer

0 votes

Answer:

x = 4/7

y = 60/7

Explanation:

3x + 4y = 36

y = x + 8

Substitute the second equation into the first since it already has the y isolated for you:

3x + 4(x + 8) = 36

3x + 4x + 32 = 36

7x = 4

x = 4/7

Take the answer you got from the equation above and plug that into the second equation:

y = 4/7 + 8

y = 60/7

To check just LS/RS both equations:

3(4/7) + 4(60/7) = 36

12/7 = 240/7 = 36

252/7 = 36

36 = 36

LS = RS

60/7 = 4/7 + 8

60/7 = 60/7

LS = RS

User James Newton
by
4.8k points