Answer:
70
Step-by-step explanation:
all the angles of a triangle sum 180, so 180 - (70 + 40) = 70
Answer:
y = -x +4
Step-by-step explanation:
2x+5y = 3y+8
Subtract 3y from each side
2x+5y-3y = 3y-3y+8
2x+2y = 8
Subtract 2x from each side
2x+2y -2x = -2x+8
2y = -2x+8
Divide by 2
2y/2 = -2x/2 +8/2
y = -x +4
Answer:
The perimeter is the distance all the way around the outside of a 2D shape. To calculate the perimeter, sum the lengths of all the sides.
Therefore, perimeter of the triangle = (2x - 8) + (2x + 5) + (30 - 3x)
Collect like terms: 2x + 2x - 3x - 8 + 5 + 30
Combine like terms: x + 27
Therefore, perimeter of triangle = x + 27
We are told that the perimeter is 25:
x + 27 = 25
Subtract 27 from both sides: x = -2
If x = -2, then the side with equation 2x - 8 = (2 x -2) - 8 = -12
A length cannot be negative, therefore the perimeter cannot equal 25.
Hi
Use Euler's formula for this for a 3D figure. F + V = E + 2, where F is the number of faces, V is the number of vertices, E is the number of edges, +2! You have enough info to fill in the formula to find that the number of vertices is 6.
Hoped I Helped
