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:
I don't really understand the question
Step-by-step explanation:
I don't know the answer
Sharon's age= 2x
Brian's age= x
(2x-5)+(x-5)= 25
3x-10=25
3x=15
x=5
Brian is 5 years old and Sharon is 10
Answer:
Confidence limit = [52.8%, 75.2%]
Step-by-step explanation:



±

where the value
will be taken from the z-table for 95% confidence interval
1-0.95= 0.05/2= 0.025
0.95+0.025= 0.0975
From the z-table the value of
corresponding to 0.0975 is 1.96
±

±

± 
% ±
%
so the confidence interval is
%
%
![[52.8, 75.2]](https://tex.z-dn.net/?f=%5B52.8%2C%2075.2%5D)
Answer:
What do you have to do with the numbers