4/d = 2/6
4*6= 2*d
24=2d
d=12
(r-3)/10=r/13
13(r-3)=10r
13r-39=10r
3r=39
r=13
Answer:
b = -7
Step-by-step explanation:
b - 7 - 6 = 15 + 5b
b - 13 = 15 + 5b
4b = -28
b = -7
Answer:
400cm²
Step-by-step explanation:
Total surface area of a prism includes the area of the top and bottom triangle sides of the prism, plus the area of all 3 rectangular sides.
Base & Bottom triangle area: 2 x [(8 x 15)/2] = 120cm²
Side triangle area: 17 x 7 + 8 x 7 + 15 x 7 = 280cm²
Total surface area = 280 + 120 = 400cm²
6x = 3x + 12 so 3x = 12 then x = 4
