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What is the value of 3 x squared plus space 4 y squared if x = 2, y = 1, and z = –3?

User Belayer
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1 Answer

3 votes

Answer:

16

Explanation:

Write the expression in algebraic form:

3x² + 4y²

Notice we only have variables "x" and "y".

Given these variables: x = 2, y = 1, and z = –3

We can ignore "z" because the variable is not in the equation.

Substitute x = 2 and y = 1 in the expression. In other words, replace "x" and "y" with the numbers they give you.

3x² + 4y²

= 3(2)² + 4(1)²

Then, simplify the expression. Remember to follow BEDMAS order (brackets, exponents, division and multiplication, addition and subtraction).

= 3(2)² + 4(1)² Solve exponents first

= 3(4) + 4(1) Solve multiplication

= 12 + 4 Solve addition

= 16 Answer

The value of 3 x squared plus 4 y squared is 16, if x = 2, y = 1, and z = -3.

User Ondrej Peterka
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