B.32 You get this because a square is perfect, which means it's equal on all sides. So 8x4=32
Answer: 
Step-by-step explanation:
1. By definition, two slopes are perpendicular if their slopes are negative reciprocals of each other. So, let's find the slope of the other line.
2. The equation given in the problem is written in Point-slope form:

Where m is the slope.
3. Therefore, the slope of its perpendicular line must be:

4. You have the point (-5,7), so you can substitute it into the point-slope formula to find the equation of the new line:

5. In slope intercept form is:

Solutions
To solve this problem we have to use the Pythagorean theorem. You can only use the Pythagorean theorem in Right Triangles. The longest side of the triangle is called the "hypotenuse". C² is the longest side so it is the hypotenuse . To calculate c² we have to do α² + β² = c².
Given
One leg of a right triangular piece of land has a length of 24 yards. They hypotenuse has a length of 74 yards. The other leg has a length of 10x yards.
First leg (24 yards) would be α
Second leg would be β
Hypotenuse (74 yards) would be c
Now we have points α β c.
a² (24) + β² ( x ) = c² (74)
Calculations
c² = α² + β²
74² = 24²+ β²
<span>5476 = 576 + </span>β²
5476 - 576 = β²
<span> </span>
<span>4900 = </span>β²
→√4900
<span> </span>
β<span> = 70 yards
</span>
<span>70 = 10x
</span>
<span>x = 70</span>÷<span>10 = 7 yards
</span>
The second leg = 7 yards

Rounding to nearest thousand gives 76,000 mg of chlorine