To solve this equation, repeatedly do the same thing to both sides of the equation until the variable is isolated on one side of the < sign and the answer on the other.

-7c - 4 < -6 + 4c
-7c < -6 + 4c + 4
-7c - 4c < -6 + 4
-11c < -2
c < \( \frac{-2}{-11} \)
c < \(\frac{2}{11}\)

According to the Pythagorean theorem, the hypotenuse squared is equal to the sum of the two perpendicular sides squared:

c² = a² + b²
c² = 9² + 9²
c² = 81 + 81
c² = 162
c = \( \sqrt{162} \)

A trapezoid is a quadrilateral with one set of parallel sides.

To factor a quadratic expression, apply the FOIL method (First, Outside, Inside, Last) in reverse. First, find the two Last terms that will multiply to produce 40 as well and sum (Inside, Outside) to equal 13. For this problem, those two numbers are 5 and 8. Then, plug these into a set of binomials using the square root of the First variable (y²):

y² + 13y + 40
y² + (5 + 8)y + (5 x 8)
(y + 5)(y + 8)

A cylinder is a solid figure with straight parallel sides and a circular or oval cross section with a radius (r) and a height (h). The volume of a cylinder is π r²h and the surface area is 2(π r²) + 2π rh.