Fill in the blank with a number to make the expression a perfect square. u^2- 18u +

Mathematics

2 answers:

topjm [15]3 years ago

8 0

Answer:

u^2- 18u +81 = (u-9)^2

Step-by-step explanation:

u^2- 18u +

Take the u coefficient

-18

Divide by 2

-18/2 = -9

Square it

(-9)^2 = 81

u^2- 18u +81 = (u-9)^2

LenaWriter [7]3 years ago

4 0

Answer:

The blank should contain 81

Step-by-step explanation:

E = u^2 - 18u + (-18/2)^2

E = (u^2 - 18u + 9^2)

E = (u - 9)^2

To be perfectly correct what you have there is a perfect square, but you need to subtract out (9/2)^2 to make it a valid statement.

E = (u - 9)^2 - 81

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5 0

3 years ago

Anyone know the answer?

uysha [10]

AB = CB
Because they are congruent
Therefore CB = 5.9
Given perimeter = 17
CB+BE+ED+DC = 17
5.9 + BE + 2.8 + 5.6 = 17
BE + 14.3 = 17
BE = 17 - 14.3
= 2.7
Hope I helped
If I did please give brainlest answer
Thanks

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malfutka [58]

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