Answer:
a = - 6
Step-by-step explanation:
Given
f(x) = 3x + 5 , then
f(a) = 3a + 5 and f(a) = - 13 , then equating the right sides
3a + 5 = - 13 ( subtract 5 from both sides )
3a = - 18 ( divide both sides by 3 )
a = - 6
1) m∠1 = 360°/8 = 45° . . . . . a regular octagon is 8-way rotationally symmetrical, so each sector is 1/8 of a circle.
2) m∠2 = (180° -45°)/2 = 67.5° . . . . . . the angles of a triangle add to 180°. The base angles of an isosceles triangle are equal.
Answer:
10.5 squared centimetres.
Step-by-step explanation:
First, find the area of that sector. We are already given that the circle is 154 squared centimetres.
We are given 90 degrees (or one fourth of the circle). Thus, divide 154 by 4 to get the area of the sector (the white area).
The area of the sector is 154/4 or 38.5
We then need to find the area of the square. After that, we can subtract the sector area (the white area) from the area of the square (the total area) to find the area of the shaded section.
The area of the square is 7*7 or 49.
Thus, the shaded portion will be 49-38.5 or 10.5 squared centimetres.