Answer:
A
Step-by-step explanation:
(3x -14) + 9x is 90 degrees, so if you add 90 it becomes 180 degrees
It is 90 degrees because you can see that there is a right angle there
Answer:
x = 15
Step-by-step explanation:
There are 2 triangles. The small triangle CDE has sides that are 8 and 20.
The big triangle CAB has sides 6+8 and 20 + x. Add the 6 and 8 which is 14. Create a proportion and cross multiply, divide, then solve for x.

Answer:
PEMDAS
P- Parenthesis
E- Exponents
M- Multiplication
D- Division
A- Addition
S- Subtraction
The first step or what you solve first is parenthesis
Step-by-step explanation:
Equations:
Quantity:: d = n + 3
Value::: 10n + 5d = 615 cents
-------------------------------------------
Modify::
d - n = 3
d + 2n = 123
--------------------------------------------
Subtract and solve for "n"::
3n = 120
n = 40 (# of nickels)
d = n+3 = 43 (# of dimes)