<span>2k² = 9 + 3k
⇒ </span><span>2k² - 9 - 3k
= 0
⇒ 2k² - 3k -9 = 0
b² - 4ac = 3² - 4*2*(-9) = 81>0
It has 2 real roots.
</span>
Answer:
1
Step-by-step explanation:
Answer:
<h2>C. 71.2 in²</h2>
Step-by-step explanation:
We have the square in the base with side a = 4in and four triangles with base a = 4in and height h = 6.9in.
The formula of an area of a square:
A = a²
Substitute:
As = 4² = 16 in²
The formula of an area of a triangle:
A = (ah)/2
Substitute:
At = [(4)(6.9)]/2 = 27.6/2 = 13.8 in²
The Surface Area:
S.A. = As + 4At
Substitute:
S.A. = 16 + 4(13.8) = 16 + 55.2 = 71.2 in²