Answer:
x=8
Step-by-step explanation:
we know that
If Quadrilateral RSTU is a rectangle
then
The measure of angle STU is a right angle
m∠STU=90°
m∠STU=m∠STR+m∠RTU
so
m∠STR+m∠RTU=90° -----> complementary angles
substitute the given values
(3x-2)+(8x+4)=90°
Solve for x
11x+2=90
11x=90-2
11x=88
x=8
Answer:
a=5
Step-by-step explanation:
Let x represent the scores. With mean and standard deviation given,
The Empirical rule states that
1) About 68% of the x values lie between 1 standard deviation below and above the mean
2) About 95% of the x values lie between 2 standard deviation below and above the mean
3) About 99.7% of the x values lie between 3 standard deviation below and above the mean
If we consider this rule, then the percentage of scores that fall within 3 standard deviation (-3 to +3) is 99% because this is closer to 99.7%
I would say either a or b