Answer:
a) -10
b) 7
Step-by-step explanation:
a) 



b) 




We can solve these equations by using substitution method where you substitute one equation to the other and solve for the value of the other variable. We do as follows:
y = 2x^2
y = –3x −1
2x^2 = –3x −1
2x^2 +3x +1 = 0
x1= -0.5
x2 = -1
y1 = 0.5
y2 = 2
<span>(A) Find the approximate length of the plank. Round to the nearest tenth of a foot.
Given that the distance of the ground is 3ft.
In order to get the length of the plank,
we can use the this one.
cos 49 = ground / plank
cos 49 = 3 / plank
plank = cos 49 / 3
plank = 0.10 ft
</span><span>(b) Find the height above the ground where the plank touches the wall. Round to the nearest tenth of a foot.
</span><span>
The remaining angle is equal to
angle = 180 - (90+49)
angle = 41
Finding the height.
tan 41 = height / ground
tan 41 = height / 3
height = tan 41 / 3
height = 0.05 ft.
(A) 0.10 feet
(B) 0.05 feet</span>
Answer:4
Step-by-step explanation: