SOLUTION: If a = 9c^2 + 4 and b = 7 + 3c, what is a in terms of b? Step by step please with formula used to solve.

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Question 346275: If a = 9c^2 + 4 and b = 7 + 3c, what is a in terms of b? Step by step please with formula used to solve.
Found 3 solutions by nyc_function, solver91311, ewatrrr:
Answer by nyc_function(2741)   (Show Source):
You can put this solution on YOUR website!
Solve b = 7 + 3c for c as step one.
b = 7 + 3c
b - 7 = 3c
(b - 7)/3 = c
Replace c with (b - 7)/3 in equation a.

a = 9c^2 + 4
a = 9[(b - 7)/3]^2 + 4
Do the math and solve for a.
This will give you the answer a in terms of b.
Understand?

Answer by solver91311(24713)   (Show Source):
You can put this solution on YOUR website!

Step 1: Solve your second equation for in terms of

Step 2: Substitute the expression containing into the first equation in place of

Step 3: Simplify.

John

My calculator said it, I believe it, that settles it

Answer by ewatrrr(24785)   (Show Source):
You can put this solution on YOUR website!
Hi,
Note: First solve for c:
b = 7 + 3c

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Substitute for c:

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a = 9(b-7)^2)/9 + 4
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