(8+12) > side > |8-12|
20 > side > 4, Then 4 cm is the solution.
Whit a triangle solver: http://triancal.esy.es/?a=8&b=12
Hey there!

Formula for the area of a triangle is (1/2)bh.
Base of this triangle is 5, height is 4.
Image attached.
Plug values into the formula:
A = (1/2)(5)(4)
Simplify.
A = (1/2)(20)
A = 10
Area of the triangle is 10 units².
Hope this helps!
B. parallelogram , rhombus , and rectangle
Answer:
x= (y+40)-(y-330)
Step-by-step explanation:
According to the information provided, the difference in their scores would be the result of subtracting Austin's SAT score from Alexandra's SAT score.
Then, as Alexandra's SAT score was 40 points above the average score this means that you have to add 40 to the average score to get her result. Also, as Austin's SAT score was 330 points below the average score, this means that you have to subtract 330 from the average score. With this you can write the expression:
x= difference in their scores
y= average score
x= (y+40)-(y-330)