Trey will read 18 pages in 45 minutes.
This is because he read 2.5 pages a minute. 25/10 = 2.5
so if we 45/2.5 = 18
Answer: choice C) -15x^4y
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Explanation:
The coefficients are -3 and 5. They are the numbers to the left of the variable terms
Multiply the coefficients to get -3*5 = -15. So -15 is the coefficient in the answer
Multiply the x terms to get x^3 times x = x^(3+1) = x^4. Notice the exponents are being added
Do the same for the y terms as well: y^2 times y^(-1) = y^(2+(-1)) = y^(2-1) = y^1 = y
So we have a final coefficient of -15, the x terms simplify to x^4 and the y terms simplify to just y
Put this all together and we end up with -15x^4y which is what choice C is showing
Google helps to so try that
Remark
The thing you must not do is write 7.182 as your answer. That is the exact answer found using a calculator.
What to do.
What you should do is multiply two rounded numbers together.
7.6 rounded is 8 roughly
0.945 is almost 1.
Your answer is 8*1 = 8 roughly. This skill is very handy when you are writing a test and you want to see if you've done the question correctly. It is easy to misplace a decimal or put in incorrect digits and this is a quick check on things like that.
9514 1404 393
Answer:
"complete the square" to put in vertex form
Step-by-step explanation:
It may be helpful to consider the square of a binomial:
(x +a)² = x² +2ax +a²
The expression x² +x +1 is in the standard form of the expression on the right above. Comparing the coefficients of x, we see ...
2a = 1
a = 1/2
That means we can write ...
(x +1/2)² = x² +x +1/4
But we need x² +x +1, so we need to add 3/4 to the binomial square in order to make the expressions equal:
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Another way to consider this is ...
x² +bx +c
= x² +2(b/2)x +(b/2)² +c -(b/2)² . . . . . . rewrite bx, add and subtract (b/2)²*
= (x +b/2)² +(c -(b/2)²)
for b=1, c=1, this becomes ...
x² +x +1 = (x +1/2)² +(1 -(1/2)²)
= (x +1/2)² +3/4
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* This process, "rewrite bx, add and subtract (b/2)²," is called "completing the square"—especially when written as (x-h)² +k, a parabola with vertex (h, k).
