To find the midpoint of a line use the midpoint formula which is M = (x1+x2/2 , y1 +y2/2) After plugging in the coordinates for your variables you should get (-1+5/2, -1+2/2) This simplifies to (2, 1/2) which is the coordinates for the middle point of the base XY.
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
The total cost would be:
$20 = two people- 2*20=40$
20 = guest
20*20=
400 would be the cost