K= 16
25x^2+40x+16x comes to be (5x+4)^2.
Question 1:Multiply both sides of the proportion by 35.
You get.
7(x-1) = 4x+2
7x-7 = 4x+2
Now, add both sides by 7 and subtract both sides by 4x
3x = 9
Divide both sides by 3
x=3
Question 2:Multiply both the numerator and the denominator of

by 3.
We want to multiply it by 3 so that the +1 and +3 become +3 and +9. +3 and +9 have a difference of 6, just like 15 and 21, which is what we want.

Set the numerator equal to the numerator and the denominator equal to the denominator.
3x+3 = 15
3x+9 = 21
If you solve both of these, you get x=4 for both.
That's your answer.
Hope this helps! :)
He made an error at step 2. First, you would flip the second fraction and multiply across. The answer would end up being 32/35.
To get the area of the shaded region, we must subtract the area of the bigger triangle on the outside and the area of the smaller triangle inside the bigger triangle.
Set up the equation:
Area of big triangle - Area of small triangle = 

So the area of the shaded region is 96.
Hope that helps!
First you look at the left side of the graph. You can tell by the shape that it is an x^3 function. also the filled in circle means inclusive. so we know that when x <= (whatever number). It is impossible to tell for sure with this graph if it is on 1. for the first part. the only answer that has less then or equal to is the last one, D. So the answer is D. You can look at the right side that it is open circle. So we know it is >. So we can see the bottom part of D has that as well