∠A = 24°
∠B = 87°
∠A = 24°
Explanation:
The sum of angles in a triangle is 180 degrees
let measure of angle A = ∠A
∠B = 15 more than three times the measure of angle A
∠B = 15 + 3∠A
∠C = 45° more than the measure of angle A
∠C = 45° + ∠A
∠A + ∠B + ∠C = 180° (sum of angles in a triangle)
∠A + 15 + 3∠A + 45° + ∠A = 180
collect like terms:
∠A + 3∠A + ∠A + 15 + 45 = 180
5∠A + 60 = 180
5∠A = 180 -60
5∠A = 120
∠A = 120/5
∠A = 24°
∠B = 15 + 3∠A = 15 + 3(24)
∠B = 87°
∠C = 45° + ∠A = 45° + 24°
∠C = 69°
Answer:
Step-by-step explanation:
x+y=10
x=10-y
x=10-5
x=5
3y= -3x+30
3(10-y)= -3(10-y)+30
30-3y= -30+3y+30
30+30-30=6y
30=6y
y=5
Answer: 310 centimeters square of paper
Explanation: to find the answer you need to know the surface area of the box. So you use the formula SA = 2ab+2bc+2ac
A=7
B=10
C=5
After inputting the values you get:
SA = 2(7)(10) + 2(10)(5) + 2(7)(5)
and after simplifying:
SA = 140+100+70
SA=310
13 x 85 = 1105
78 + 91 = 169
169 / 1105 = 6.5