Answer: 10.5 ft^2
Step-by-step explanation:
![A=\frac{a*b}{2} \\\\A=\frac{7*3}{2}\\\\A=10.5ft^{2}](https://tex.z-dn.net/?f=A%3D%5Cfrac%7Ba%2Ab%7D%7B2%7D%20%5C%5C%5C%5CA%3D%5Cfrac%7B7%2A3%7D%7B2%7D%5C%5C%5C%5CA%3D10.5ft%5E%7B2%7D)
Answer:
Clarissa will take 10 hours by herself
Step-by-step explanation:
Let s = time for shawna
s-5 = time for clarissa
The formula for determining the time is
1/a + 1/b = 1/c where a and b are the times alone and c is the time together
1/s + 1/(s-5) = 1/6
Multiply each side by 6s(s-5) to clear the fractions
6s(s-5) ( 1/s + 1/(s-5)) = 1/6 *6s(s-5)
Distribute
6(s-5) + 6s = s(s-5)
Distribute
6s -30 +6s = s^2 -5s
Combine like terms
12s -30 = s^2 -5s
Move everything to the right
0 = s^2 -5s -12s +30
0 = s^2 -17s +30
Factor
0 = ( s-15) (s-2)
Using the zero product property
s-15 =0 s-2 =0
s =15 s=2 ( This is not a reasonable answer since it is less than the time together)
s=15
s-5 = 10
Clarissa will take 10 hours by herself
a is SSS, c is SAS and d is ASA, all good congruent triangle theorems.
b is AAA, good to show similar triangles, not necessarily congruent triangles.
Answer: b
4.99x2=9.98. 11.45x3=34.35. 9.98+34.35=44.33. 6% of 44.33 is 2.6598. 44.33+2.6598=46.9898. So the total is $46.99