Answer:
f = -14
Step-by-step explanation:
given:
4 − (–5f) = –66
4 + 5f = -66 ( subtract 4 from both sides)
5f = -66 - 4
5f = -70 (divide both sides by 5)
f = (-70) / 5
f = -14
1. Find the cost of levelling the ground in the form of a triangle having the sides 51 m, 37 m and 20 m at the rate of ₹ 3 per m².
a = 51 m, b = 37 m, c = 20 m
semiperimeter: p = (51+37+20):2 = 54 m
Area of triangle:

Rate: ₹ 3 per m².
Cost: ₹ 3•306 = ₹ 918
2. Find the area of the isosceles triangle whose perimeter is 11 cm and the base is 5 cm.
a = 5 cm
a+2b = 11 cm ⇒ 2b = 6 cm ⇒ b = 3 cm
p = 11:2 = 5.5

3. Find the area of the equilateral triangle whose each side is 8 cm.
a = b = c = 8 cm
p = (8•3):2 = 12 cm

4. The perimeter of an isosceles triangle is 32 cm. The ratio of the equal side to its base is 3 : 2. Find the area of the triangle.
a = 2x
b = 3x
2x + 2•3x = 32 cm ⇒ 8x = 32 cm ⇒ x = 4 cm ⇒ a = 8 cm, b = 12 cm
p = 32:2 = 16 cm

2.1 is less than 2.42 and greater than 2.0
Answer:
0.982 *
= 3.085 cubic units
Step-by-step explanation:
To find the volume of the solid generated by a region that is bounded by lines where x = 0 , x (b) = 2 we apply the formula given in the attachment below
the required region boundaries are
y = e^-x2 , y = 0 , x = 0, x = b ( b >0)
attached below is a detailed solution of the problem
Answer: The answer is x^2+2xy+2y^2–3x–3y–1
Step-by-step explanation: Move 2 to the left of y^2.