Question

I'm really confused right now
Okay so my problem tells me to write a function rule for the area of a triangle whose base is 4 feet more than its height.
The choices are :



A. A = 0.5h2 + 4h; 42 ft2




B. A = 4h − 0.5h2; 6 ft2


C. A = 0.5h2 + 2h; 30 ft2


D. A = 0.5h2 − 2h; 6 ft2

Please explain and not just give me the answer. Believe it or not I actually don't want to fail Algebra.

Answer 1

\(area=\frac{1}{2}b*h\)
if b=h+4
replace it and you'll get \(a=\frac{1}{2}(h)(h+4)=\frac{1}{2}(h^2+4h)=\frac{h^2}{2}*2h\)

Answer 2

on the last part, bibby probably meant to say \(\Large \frac{h^2}{2} + 2h\) and not \(\Large \frac{h^2}{2} * 2h\)

Answer 3

keep in mind that

\[\Large \frac{h^2}{2} = \frac{1}{2}*h^2 = 0.5h^2\]

since 1/2 = 0.5

Answer 4

I'm not sure why there's a part 2 that says 30 but yeah I meant \(0.5h^2+2h\)

Answer 5

I'm guessing something got cut off like

"Part 2: Find the area when h = ... "

Answer 6

yes

Answer 7

0.5h^2+2h=30
0.5(h^2+4h)=30
h^2+4h=60
h^2+4h-60=0
(h-6)(h+10)=0
h=6

Answer 8

hey guys, sorry i didn't know someone would answer so quick. i think i understand so thanks . I just put part 1 up cuz i thought that if someone could explain Part 1 i could do Part2, so thank you ! Bibby and Jim r the best!

Answer 9

well once they give you h=6 you just plug it into the equation we found in part 1.
0.5*6*6+2*6
0.5*36+12
18+12=30