9514 1404 393
Answer:
(b) 38.5
Step-by-step explanation:
The polygon is a trapezoid with bases 4 and 7 and height 7. Its area is given by the formula ...
A = (1/2)(b1 +b2)h
A = (1/2)(4 +7)(7) = 77/2
A = 38.5 . . . . square units
Answer:
Triangle 1: x = 80 degrees, acute
Triangle 2: x = 10 degrees, right
Step-by-step explanation:
Triangle 1:
By the Sum of Interior Angles Theorem, all the angles inside the triangle adds up to 180 degrees. So, set up this equation:

Solve for x:

So, x = 80 degrees
Because all the angles are less than 90 degrees, this is an acute triangle.
Triangle 2:
By the Sum of Interior Angles Theorem, all the angles inside the triangle adds up to 180 degrees. So, set up this equation (with the right angle given):

Solve for x:

So, x = 10 degrees
Because there is an angle measuring 90 degrees, this is a right triangle.
Answer:
x = -2 y = -8
Step-by-step explanation:
13x - 6y = 22
x - y = 6
6(x-y) = 6*6
6x - 6y = 36
subtract both the equations
13x - 6x -6y + 6y = -14
7x = -14
x = -2
13*-2 -6y=22
-26 -6y=22
-6y = 48
y = -8
answer: x = -2 y = -8