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3 years ago

30+2k+5k=100 What is k?

Mathematics

2 answers:

wlad13 [49]3 years ago

7 0

Answer:

k = 10

Step-by-step explanation:

30+2k+5k=100

Combine like terms

30 + 7k = 100

Subtract 30 from each side

30+7k-30 = 100-30

7k = 70

Divide each side by 7

7k/7 = 70/7

k = 10

Alenkasestr [34]3 years ago

4 0

Answer:

k=10

Step-by-step explanation:

We are given the equation:

30+5k+2k=100

We want to find k, therefore we must isolate k on one side of the equation.

First, combine like terms on the left side of the equation. 5k and 2k can be added together.

30+5k+2k=100

30+(5k+2k)=100

30+7k=100

30 is being added to 7k. The inverse of addition is subtraction. Subtract 30 from both sides of the equation.

30-30+7k=100-30

7k= 100-30

7k= 70

k is being multiplied by 7. The inverse of multiplication is division. Divide both sides by 7.

7k/7=70/7

k=70/7

k= 10

The solution to the equation 30+5k+2k=100 is k=10

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