not the GREATEST at math but try 50
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

X = 5 - 3y
x = 2y - 10
5 - 3y = 2y - 10
<u> + 3y + 3y </u>
5 = 5y - 10
<u>+ 10 + 10</u>
<u>15</u> = <u>5y</u>
5 5
3 = y
x = 2y - 10
x = 2(3) - 10
x = 6 - 10
x = -4
(x, y) = (-4, 3)
Answer:
Red = 10 cm, blue = 14 cm
Step-by-step explanation:
<em>Let the length of each red rod be </em><em>r </em><em>and each blue rod be </em><em>b</em>
<u>Then we have:</u>
<u>Multiply the first equation by 3 and the second one by 2:</u>
<u>Add the equations to eliminate one of variables:</u>
<u>Find the value of b:</u>
- 3*10 -2b = 2
- 30 - 2 = 2b
- 2b = 28
- b = 14 cm
sin = 3/7
1 = sin²0 + cos²0
cos²0 = 1 - 9/49
cos²0 = 40/49
cos0 = √(40) / 7
since its in Quadrant 2 the sin is positive and cos is negative
cos0 = - √(40) / 7