Answer:
D
Step-by-step explanation:
We name the corners of the triangle as the attached image.
As we can see, triangle ABC is a right-angled triangle with Angle B equal to 90 degree.
As ABC is a right triangle, so that total measures of angle A and angle C is 90 degree
=> m∠A + m∠C = 90
=> m∠A + 45 = 90
=> m∠A = 90 - 45 = 45
=> m∠A = m∠C
So that ABC is also an isosceles triangle.
=> AB = AC = x
As ABC is a right triangle, according to Pythagoras theorem, we have the following equation:
AB^2 + BC^2 = AC^2
=> x^2 + x^2 = 20^2
=> 2.x^2 = 400
=> x^2 = 400/2 = 200
=> x = ≈ 14.14
So that x ≈ 14.14, the correct answer is D
Answer:
47.45 cm³
Step-by-step explanation:
Radius
= 10 ÷ 2π
= 5/π
Volume
= π(5/π)²(6)
= 150/π
= 47.45 cm³
A motorist drove 150 miles in the morning and;
50 miles in the afternoon
His average rate in the morning was twice his average rate in the afternoon
He spent 5hrs driving
Let the times spent driving in the morning be x
Average speed = Distance ÷ time
= 2()
Cross multiplying gives;
750 - 150x = 100x
250x = 750 , x =3
Average speed in the morning is 150/3 = 50miles/hr
Average speed in the afternoon = 50/(5-3) = 25miles/hr
Lim x->1 (x^2+8x-2)
substitute x =1
= 1^2 +8(1)-2
= 1 +8 -2
= 7
So the limit = 7