Answer:
y = 4.125x + 496.25
Step-by-step explanation:
Set the data up as points. Then deal with the points.
Givens
(30,620)
(70,785)
y2 = 785
y1 = 620
x2 = 70
x1 = 30
Formula
Slope = (y2 - y1) / (x2 - x1)
Solution
Slope = (785 - 620)/(70 - 30)
Slope = 165 / 40
Slope = 4.125
===================
Now you need the y intercept. Either one of the two given points will give you that.
y = 620
x = 30
m = 4.125
y = mx + b
620 = 4.125*30 + b
620 = 123.75 + b
620 - 123.75 + b
b = 496.25
Answer:
12
Step-by-step explanation:
First of all, we compute the points of interest, i.e. the points where the curve cuts the x axis: since the expression is already factored, we have

Which means that the roots are

Next, we can expand the function definition:

In this form, it is much easier to compute the derivative:

If we evaluate the derivative in the points of interest, we have

This means that we are looking for the equations of three lines, of which we know a point and the slope. The equation

is what we need. The three lines are:
This is the tangent at x = -2
This is the tangent at x = 0
This is the tangent at x = 1
They would be alternate exterior so they would have to to be equal
2k + 11 = 131
-11 -11
2k = 120
---- -----
2k 2k
k = 60
Answer:
Area of trapezium = 4.4132 R²
Step-by-step explanation:
Given, MNPK is a trapezoid
MN = PK and ∠NMK = 65°
OT = R.
⇒ ∠PKM = 65° and also ∠MNP = ∠KPN = x (say).
Now, sum of interior angles in a quadrilateral of 4 sides = 360°.
⇒ x + x + 65° + 65° = 360°
⇒ x = 115°.
Here, NS is a tangent to the circle and ∠NSO = 90°
consider triangle NOS;
line joining O and N bisects the angle ∠MNP
⇒ ∠ONS =
= 57.5°
Now, tan(57.5°) = 
⇒ 1.5697 = 
⇒ SN = 0.637 R
⇒ NP = 2×SN = 2× 0.637 R = 1.274 R
Now, draw a line parallel to ST from N to line MK
let the intersection point be Q.
⇒ NQ = 2R
Consider triangle NQM,
tan(∠NMQ) = 
⇒ tan65° =
⇒ QM =
QM = 0.9326 R .
⇒ MT = MQ + QT
= 0.9326 R + 0.637 R (as QT = SN)
⇒ MT = 1.5696 R
⇒ MK = 2×MT = 2×1.5696 R = 3.1392 R
Now, area of trapezium is (sum of parallel sides/ 2)×(distance between them).
⇒ A = (
) × (ST)
= (
) × 2 R
= 4.4132 R²
⇒ Area of trapezium = 4.4132 R²