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.

-3b + 9 < \( \frac{b}{7} \)
7 x (-3b + 9) < b
(7 x -3b) + (7 x 9) < b
-21b + 63 < b
-21b + 63 - b < 0
-21b - b < -63
-22b < -63
b < \( \frac{-63}{-22} \)
b < 2\(\frac{19}{22}\)

Angles around a line add up to 180°. Angles around a point add up to 360°. When two lines intersect, adjacent angles are supplementary (they add up to 180°) and angles across from either other are vertical (they're equal).

The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:

b² + 7b + 12 = 0
(b + 3)(b + 4) = 0

For this expression to be true, the left side of the expression must equal zero. Therefore, either (b + 3) or (b + 4) must equal zero:

If (b + 3) = 0, b must equal -3
If (b + 4) = 0, b must equal -4

So the solution is that b = -3 or -4

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 equal sign and the answer on the other.

-2a + 9 = 5 - 3a
-2a = 5 - 3a - 9
-2a + 3a = 5 - 9
a = -4

The formula for area is πr². Radius is circle \( \frac{diameter}{2} \):

r = \( \frac{d}{2} \)
r = \( \frac{10}{2} \)
r = 5
a = πr²
a = π(5²)
a = 25π