Answer:
5 cm
Step-by-step explanation:
We khow that the altitude of this triangle is 1cm shorter than the base
- Let H be our altitude and B our base and A the area of the triangle
- A= (B*H)/2 ⇒ 15=(B*H)/2
- H is 1cm shorter than B ⇒ B=H+1
- H*(H+1)/2=15 ⇒ H*(H+1)=30⇒ H²+H=30⇒H²+H-30+0
that's a quadratic equation . Let's calculate the dicriminant .
Let Δ be the dicriminant
- a=1
- b=1
- c= -30
- Δ=b²-4*a*c = 1²-4*1*(-30)=1+4*30=121≥0
- Δ≥0⇔ that we have two solutions x and y
- x= (-1-
)/2= (-1-11)/2= -6 - y= (-1+
)/2= 10/2 = 5
We have a negative value and a positive one
The altitude is a distance so it can't be negative
H= 5cm
Answer:
If f(−x) = −f(x), then the graph of f(x) is symmetrical with respect to . A function symmetrical with respect to the y-axis is called an even function. A function that is symmetrical with respect to the origin is called an odd function.
Answer:
276 4/7 ft
Step-by-step explanation:
Let r1 represent the radius of the inner circle. Then its circumference in feet is ...
C = 2πr
66 = 2π(r1)
If the radius of the outer circle is (r1 +44), then its circumference is ...
C = 2π(r1 +44) = 2π(r1) +2π(44)
C = 66 +88π
Then the difference in the circumferences is ...
(66 +88π) - (66) = 88π
Using the given value of π, the difference in circumferences is ...
(88 ft)(22/7) = 1936/7 ft = 276 4/7 ft
Let the distance of the first part of the race be x, and that of the second part, 15 - x, then
x/8 + (15 - x)/20 = 1.125
5x + 2(15 - x) = 40 x 1.125
5x + 30 - 2x = 45
3x = 45 - 30 = 15
x = 15/3 = 5
Therefore, the distance of the first part of the race is 5 miles and the time is 5/8 = 0.625 hours or 37.5 minutes
The distance of the second part of the race is 15 - 5 = 10 miles and the time is 1.125 - 0.625 = 0.5 hours or 30 minutes.
Answer:
-4
Step-by-step explanation:
2/5 times -10 = -4