Question

6c^2 - 5d + 8 when c =5 and d=4

Answer 1

138

Explanation:

First, we can simply replace the variables with their numerical values.

Whenever you see a number with a letter (variable) in front of it, this means to multiply.

c=5 and d=4

6 × 5^2 - 5 × 4 + 8

Since there are multiple operations in this expression, we must use PEMDAS.

• Parenthesis

• Exponentiation (exponents)

• Multiplication/Division (Solve whichever comes first)

• Addition/Subtraction (Solve whichever comes first)

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Now, we can apply the operations.

There are no parenthesis.

In this expression, exponents are present.

6 × 5^2 - 5 × 4 + 8

6 × 25 - 5 × 4 + 8

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There is multiplication.

6 × 25 - 5 × 4 + 8

150 - 5 × 4 + 8

150 - 20 + 8

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There is subtraction.

150 - 20 + 8

130 + 8

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There is addition.

130 + 8

158

Therefore, 6 × 5^2 - 5 × 4 + 8 = 138.