2((x+2)(x+2)}-4=28
2{x^2 + 4x + 4}-4=28
2x^2 +4x=28
2(x^2+2x)=28
x^2+2x=28/2
x^2+2x=14
Answer:
40, 60 and 80 degrees.
Step-by-step explanation:
Let the smallest angle be x degrees. Then:
The 3 angles are x, x + 40 and x + 20.
As there are 180 degrees in a triangle:
x + x + 40 + x + 20 = 180
3x = 180 -40--20 = 120
x = 40 degrees.
The other 2 angles are 60 and 80 degrees.
Answer:
Step-by-step explanation:
Answer:
D
Step-by-step explanation:
We calculate the z-score for each
Mathematically;
z-score = (x-mean)/SD
z1 = (1.9-2.1)/0.2 = -1
z2 = (2.3-2.1)/0.2 = 1
So the proportion we want to calculate is;
P(-1<x<1)
We use the standard score table for this ;
P(-1<x<1) = P(x<1) -P(x<-1) = 0.68269 which is approximately 68%
