How do you evaluate 2x^2 - 2z^4 + y^2 - x^2 + z^42x2−2z4+y2−x2+z4 if x = -4, y = 3, and z = 2x=−4,y=3,andz=2?

1 Answer
Johnson Z.
Jun 30, 2016

99

Explanation:

Given,

2x^2-2z^4+y^2-x^2+z^42x2−2z4+y2−x2+z4

Knowing that x=-4, y=3, z=2x=−4,y=3,z=2, replace each variable with its appropriate number.

=2(-4)^2-2(2)^4+(3)^2-(-4)^2+(2)^4=2(−4)2−2(2)4+(3)2−(−4)2+(2)4

Recall that a number raised to a power nn means to multiply the number by itself nn times. Hence,

=2(color(red)(-4)*color(red)(-4))-2(color(blue)2*color(blue)2*color(blue)2*color(blue)2)+(color(darkorange)3*color(darkorange)3)-(color(purple)(-4)*color(purple)(-4))+(color(teal)2*color(teal)2*color(teal)2*color(teal)2)=2(−4⋅−4)−2(2⋅2⋅2⋅2)+(3⋅3)−(−4⋅−4)+(2⋅2⋅2⋅2)

Simplify.

=2(color(red)16)-2(color(blue)16)+(color(darkorange)9)-(color(purple)16)+(color(teal)16)=2(16)−2(16)+(9)−(16)+(16)

=32-32+9-16+16=32−32+9−16+16

=color(green)(|bar(ul(color(white)(a/a)color(black)9color(white)(a/a)|)))

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