Answer:
D
Step-by-step explanation:
For simplify the work we can start to factorise all the possibles expressions:
2x + 8.
8 is multiple of 2, so it can became
2(x+4)
x^2 - 16 this is a difference of two squares, so it can be rewritten as:
(x+4)(x-4)
x^2 + 8x + 16
we have to find two numbers whose sum is 8 and whose product is 16
the two number are 4 and 4
it becames:
(x+4)(x+4)
x+ 4 can‘t be simplified
if we look at the expression, we can find that x-4 appears at the numerator so
x^2 - 16 must be at numerator
but the second factor (x+4) doesn’t appear, so has been simplified. This situation can be possible only in the D option
in fact
(x+4)(x-4)/2(x+4) * (x+4)/(x+4)(x+4)
it became
(x+4)(x-4)/2 * 1/(x+4)(x+4)
(x-4)/2(x+4)
Answer:
The precipitation for both March and April was 8 7/8 inches below average
Step-by step explanation;
For the month of march, precipitation was 6 1/2 inches less than average
For the month of April, precipitation was 2 3/8 inches left.
Now we want to calculate how many inches less than average was precipitation in both wants
What we simply do here is to add the inches with which they were both left than average in both months
That would be;
6 1/2 + 2 3/8
= 13/2 + 19/8 = (52 + 19)/8 = 71/8 = 8 7/8 inches
A= 58°B= 83° because you add the straight angle which is 90 plus the other number and subtract it by 180 because a triangle has 180°
It's a trick question. There are an infinite number of mixed numbers between 3 and 4 that can multiply to equal 12 (for example, 3 and 3/7 times 3 and 1/2), but there are no mixed numbers between 3 and 4 that can multiply to equal 9. 3 times 3 is not between them but is 3, but that quantity is excluded because 3<x<4. Anything even a small bit above the number 3 would have to be multiplied by 2 and some fraction, which would not be between 3 and 4.
For x^2-49
this is a diffarence of two perfect squares. I suggest that this is memorised.
a^2-b^2=(a-b)(a+b)
so x^2-7^2=(x-7)(x+7)
so to solve x^2+x-56 you want to find out what two numbers add to 1 and multiply to make -56
since -56 is negative we know that the two number are difarent signs so that eliminatess answers B and D.
if we try answer C -8+7=-1 so the answer is not C because we want +1 not -1
then we see that 8+(-7)=1 so the answer is A