Answer:
149.84
Step-by-step explanation:
Answer:
3 or
C
Step-by-step explanation:
(45 - 3x)^1/2 = x - 9 Square both sides
45 - 3x = x^2 - 18x + 81 Switch sides
x^2 - 18x + 81 = 45 - 3x Add 3x to both sides
x^2 - 15x + 81 = 45 Subtract 45 from both sides
x^2 - 15x + 36 = 0 Factor
(x - 12)(x - 3) =0
The answers are
x = 12
x = 3
Now the question asks which is extraneous. The answer will be which ever number won't solve the original equation. Looking at it right now, both look OK.
(45 - 3*12)^1/2 = 12 - 9
(45 - 36)^1/2 = 3
(9)^1/2 = 3
So 12 is a proper solution.
What about 3?
(45 - 3*3)^1/2 = 12 - 3
(45 - 9)^1/2 = 9
36^1/2 = 9
6 does not = 9
The extraneous solution is x = 3
Answer:
1. Isosceles Triangle
2. ∠D = 160°
Step-by-step explanation:
1.
7x + 5 + x + 20 + 2x + 5 = 180 (all angles in a triangle add up to 180)
10x = 150
x = 15°
∠A = 7x + 5
sub x = 15°
∠A = 7x + 5
∠A = 120°
∠B = x + 20
x = 15
∠B = 35
∠C = 2x + 5
x = 15
∠C = 35
Base angles are the same, so this triangle is isosceles
2.
3x + (2x - 1) + (x + 3) + (3x - 3) + (x - 2) = 540 (all angles in a 5-sided polygon equals 540°)
10x = 540 + 1 - 3 + 3 + 2
10x = 543
x = 54.3
∠D = 3x - 3
x = 54.3
∠D = 159.9
if you round it, it would about 160°