34.5=4h+7c
(34.5-7c)/4=h
Put h= (34.5-7c)/4 into another equation
30.5=8h+3c
30.5=2(34.5-7c)+3c
30.5=69-14c+3c
11c=38.5
c=38.5/11
Put c=38.5/11 into one of the equations
to calculate the h.
Answer:
7/11
Step-by-step explanation:




No, because if you divide 23 / 4, you get 5.75. You can't get 0.75th of a kid. So it is not reasonable, because it is a decimal, and not a whole number.
Hope this helped! ☺♥
Answer:

Step-by-step explanation:
we know that
An exterior angle of a triangle is equal to the sum of the opposite interior angles.
see the attached figure to better understand the problem
so
∠DEF=∠ECD+∠CDE
substitute the given values

solve for x
Combine like terms

Group terms



Find the measure of angle CDE

substitute the value of x

Answer:
As shown in picture, this is a trapezoid.
The area of a trapezoid is calculated by:
A = (base1 + base2) x height x (1/2)
To work out A, we need to find out base1, base2, and height.
base1 = YZ = 
base2 = XW =
Otherwise, the height (distance between base1 and base2) is 4 as shown in picture.
=> A = (3 + 7) x 4 x (1/2) = 20
Hope this helps!
:)