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

You might be interested in

Write the expression x^-5 in positive exponential form <br> Answer for brainliest!

vladimir1956 [14]

It's 1/x^5

Hope it helps

8 0

3 years ago

Read 2 more answers

caleb and emily are standing 100 yards from each other. caleb looks up at a 45 degree angle to see a hot air balloon. Emily look

Sunny_sXe [5.5K]

Check the picture below.

thus then

$\bf \begin{cases}
y=100-a\\
y=a\sqrt{3}
\end{cases}\implies 100-a=a\sqrt{3}\implies 100=a+a\sqrt{3}
\\\\\\
100=a(1+\sqrt{3})\implies \boxed{\cfrac{100}{1+\sqrt{3}}=a}
\\\\\\
\textit{what is the altitude \underline{y} then?}\qquad y=100-a
\\\\\\
y=100-\cfrac{100}{1+\sqrt{3}}\implies y\approx 63.39745962156~yards$

8 0

3 years ago

Read 2 more answers

Watch help video If you place a 13-foot ladder against the top of a 12-foot building, how many feet will the bottom of the ladde

riadik2000 [5.3K]

$\begin{gathered} X\text{ will represent the bottom of the ladder fom the bottom of the building} \\ U\text{sing pythagoras Theorem} \\ (Hyp)^2=(opp)^2+(Adj)^2 \\ 13^2=x^2+12^2 \\ 169=x^2\text{ +144} \\ 169-144=x^2 \\ 25=x^2 \\ x^2\text{ = 25} \\ x\text{ = }\sqrt[]{25} \\ x\text{ = 5foot} \end{gathered}$