For this case we have:
way 1:
Common factor 3 in the expression:
Way 2:
Write the number 12 as the sum of 4 times 3:

Then, for associative property:
It is an irrational number. A number is rational if it can be expressed as a quotient of 2 integer numbers. Number π2 cannot be expressed as a quotient of integers, so it is an irrational number.
Answer:
E
Step-by-step explanation:
The external angle of a triangle is equal to the sum of the 2 opposite interior angles.
8x + 15 is an external angle of the triangle, thus
8x + 15 = 3x + 20 + 4x + 5, that is
8x + 15 = 7x + 25 ( subtract 7x from both sides )
x + 15 = 25 ( subtract 15 from both sides )
x = 10
Thus none of them on the list → E
Answer:
Only the firsts and fourth choices (
and
)
Step-by-step explanation:
Turn the equation into words:
"A number plus 9"

"Multiplied by
"

"Is equals to -18"

Distribute to find the second equation:

Answer:
402m
Step-by-step explanation:
Set this up as a triangle and use trig to solve it:
tan(45) = y/402
y = 402*tan(45)
substitute: tan(45) = 1
y = 402 * 1
y = 402m