Answer: a) Yes, there is enough fance
b) 58.1° and 47.9°
c) The city will not approve, because 1/3 of the area is just 2220.5ft²
Step-by-step explanation:
a) using law of cosines: x is the side we do not know.
x² = 126² + 110² - 2.126.110.cos74°
x² = 20335.3
x = 142.6 ft
So 150 > 142.6, there is enough fance
b) using law of sine:
sin 74/ 142.6 = sinα/126 = sinβ/110
sin 74/ 142.6 = sinα/126
0.006741 = sinα/126
sinα = 0.849
α = sin⁻¹(0.849)
α = 58.1°
sin 74/ 142.6 = sinβ/110
sin 74/ 142.6 = sinβ/110
0.006741 = sinβ/110
sinβ = 0.741
β = sin⁻¹(0.741)
β = 47.9°
Checking: 74+58.1+47.9 = 180° ok
c) Using Heron A² = p(p-a)(p-b)(p-c)
p = a+b+c/2
p=126+110+142.6/2
p=189.3
A² = 189.3(189.3-126)(189.3-110)(189.3-142.6)
A = 6661.5 ft²
1/3 A = 2220.5
So 2300 > 2220.5. The area you want to build is bigger than the area available.
The city will not approve
Answer:
I will answer in a general way because the options are not given.
We know that the area of model A is smaller than the area of model B.
For model A, we have 72 shaded sections, out of 100.
Then the quotient of model A is:
72/100 = 0.72
For model B we have 10 sections, and x shaded ones.
Because model B is greater than model A, we know that:
x/10 should be larger than 72/100
then we have the inequality:
x/10 > 0.72
x > 0.72*10
x > 7.2
And we can not have more than 10 shaded sections (because there is a total of 10 sections) then:
10 ≥ x > 7.2
Then x can be any whole number in that interval.
the possible values of x are:
x = 8
x = 9
x = 10
Answer: C. (-4, -2)
<u>Step-by-step explanation:</u>
First, eliminate one of the variables and solve for the remaining variable:
2x - 5y = 2 → 3(2x - 5y = 2) → 6x - 15y = 6
3x + 2y = -16 → -2(3x + 2y = -16) → <u> -6x - 4y = 32</u>
-19y = 38
y = -2
Next, replace "y" with -2 into either of the original equations to solve for x:
2x - 5y = 2
2x - 5(-2) = 2
2x + 10 = 2
2x = -8
x = -4
x = -4, y = -2
<u>Check:</u>
Plug in the x- and y-values into the other original equation:
3x + 2y = -16
3(-4) + 2(-2) = -16
-12 + -4 = -16
-16 = -16 
Answer: A. The first one
Step-by-step explanation:
