Ok so here u go
<span>Simplifying
6(2x + -11) + 15 = 21 Reorder the terms:
6(-11 + 2x) + 15 = 21
(-11 * 6 + 2x * 6) + 15 = 21
(-66 + 12x) + 15 = 21 Reorder the terms:
-66 + 15 + 12x = 21 Combine like terms: -66 + 15 = -51
-51 + 12x = 21 Solving
-51 + 12x = 21
Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right.
Add '51' to each side of the equation.
-51 + 51 + 12x = 21 + 51
Combine like terms: -51 + 51 = 0
0 + 12x = 21 + 51
12x = 21 + 51 Combine like terms: 21 + 51 = 72
12x = 72
Divide each side by '12'.
x = 6
Simplifying
x = 6</span>
It’s the one that is marked as (3,3)
When x=0, y=4...
Therefore:
4=a*b⁰
b⁰=1, so a=4.
----------
When x=1, y=2...
Therefore:
2=4*b¹
4b=2
b=2/4
So... b=1/2.
This means that:
y=4*((1/2)^x)
I think it’s increase of 4%
This triangle is a 30-60-90 triangle, which you can just find by solving for the unknown angle in the triangle, making it a 30-60-90 triangle.
You'll need to memorize the side lengths for these triangles, but the side opposite from the hypotenuse (x in this case), will be half the length of the hypotenuse.
Meaning that 
So 
Hope this helps.
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