Answer:
C. 2.8 * 10^-5
Step-by-step explanation:
Ok so its been a while since I've done these but pretty sure c is the answer. (Double check to make sure I'm correct)
Factor out a GCF of 4, then you are left with perfect squares.
4(100-9x^2)
Factor what is left as a difference of perfect squares (the outside and inside terms from FOIL should cancel out which is why each parenthesis has a different sign
f(10+3x)(10-3x)
Answer:
164.8
Step-by-step explanation:
I used a calculator :)
One way of doing it is by using the properties of summing things, like factoring out the minus sign:
<span><span>∑<span>n=2</span>8</span><span>−(n−5)</span>=−<span>∑<span>n=2</span>8</span><span>(n−5)
</span></span>
and splitting it up into two parts and again factor
<span>=−<span>(<span><span>∑<span>n=2</span>8</span><span>n−5<span>∑<span>n=2</span>8</span>1</span></span>)
</span></span>
The last sum is just counting how many numbers there are from 2 to 8, which is 7 (you can do it on your fingers). The first one can be calculated fast if we are clever and use this identity:
<span><span>∑<span>n=1</span>m</span>n=<span><span>m(m+1)</span>2
</span></span>
So what we get is
<span><span>=−<span>(<span>−1+<span><span>8(8+1)</span>2</span>−7</span>)</span>=8−72/2=8−36=−28.</span></span>
Answer:
Oranges is 1.80
Apples is .90
Bananas is .50
So far she spent 3.20
She will still have .45 cents and can use it to but 3 pears
So this answer is 3 pears
Step-by-step explanation:
