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Which is the best first step when solving the following system of equations?

5C+40= 10
3C+2d=16

Which is the best first step when solving the following system of equations? 5C+40= 10 3C-example-1

2 Answers

5 votes
-2 would be your answer




Hope it helps
User Simianarmy
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3.8k points
5 votes

Answer:

multiply the second equation by - 2

Explanation:

Given the 2 equations

5c + 4d = 10 → (1)

3c + 2d = 16 → (2)

Multiplying (2) by - 2 and adding to (1) will eliminate d

- 6c - 4d = - 32 → (3)

Add (1) and (3) term by term to eliminate d

- c + 0 = - 22

- c = - 22 ( multiply both sides by - 1 )

c = 22

Substitute c = 22 into either of the 2 equations and solve for d

Substituting into (2)

3(22) + 2d = 16

66 + 2d = 16 ( subtract 66 from both sides )

2d = - 50 ( divide both sides by 2 )

d = - 25

solution is c = 22, d = - 25

User VMois
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