Answer:
13) Angle A is 30°
14) Angle A is 45°
15) Angle A is 40°
16) Angle A is 40.5°
Step-by-step explanation:
By the angle sum theorem for the interior angles of a triangle, we have;
13) 130° + 2·x + 3·x = 180°
∴ 2·x + 3·x = 180° - 130° = 50°
2·x + 3·x = 5·x = 50°
x = 50°/5 = 10°
∠A = 3·x = 3 × 10° = 30°
∠A = 30°
14) 3·x + 9 + 4·x + 9 + 78° = 180°
7·x + 18 + 78° = 180°
7·x = 180° - (18 + 78)° = 180° - 96° = 84°
x = 84°/7 = 12°
∠A = 3·x + 9 = 3 × 12° + 9 = 45°
∠A = 45°
15) 90° + x + 51 + x + 61 = 180°
∴ x + 51 + x + 61 = 180° - 90° = 90°
2·x + 112 = 90°
2·x = (90 - 112)° = -22°
x = -22°/2 = -11°
x = -11°
∠A = x + 51 = -11° + 51 = 40°
∠A = 40°
16) x + 79 + x + 49 + 70° = 180°
x + x = (180 - 70 - 79 - 48)° = -17°
2·x = -17°
x = -17°/2 = -8.5°
x = -8.5°
∠A = x + 49 = (-8.5 + 49)° = 40.5°
∠A = 40.5°.
It’s bull Peter C your welcome :)
x/.75=x-56/0.4
0.4x=.75x-42
-0.35x=-42
x=120
I set up a proportion in which x=the tank when it is 3/4 full. When the tank is 3/4 full, solving the proportion tells us the x=120 litres. 120/3=40, and 120+40 is 160, showing that a tank completely full would indeed hold 160 litres.
Hope this helps!
Answer:
The answer is c!
Step-by-step explanation:
Answer:
The Answer is that Senior Citizen Tickets cost: $4 and Child tickets cost: $7.
Step-by-step explanation:
Let s = the cost of senior citizen tickets
Let c = the cost of child tickets
The number of tickets sold for each type added together equals the sales for each day. Equations below:
Day 1
3s + 9c = $75
Solve for s:
3s = 75 - 9c
s = 25 - 3c
Day 2
8s + 5c = $67
By substitution:
8(25 - 3c) + 5c = 67
200 - 24c + 5c = 67
-19c = -133
c = -133 / -19 = $7 cost for child tickets.
Solve for s:
s = 25 - 3c
s = 25 - 3(7)
s = 25 - 21 = $4 cost for senior citizen tickets.
Proofs:
Day 1
3s + 9c = $75
3(4) + 9(7) = 75
12 + 63 = 75
75 = 75
Day 2
8s + 5c = $67
8(4) + 5(7) = 67
32 + 35 = 67
67 = 67