Answer:
F = 7: 16
Step-by-step explanation:
Equating 1 : x and 7:2
x = 2:7
Substituting x into the other equation we have
1: 16/7
Which is equal to 7: 16

Considering the diagram.
is shown to be acute, so
.
Angles in a triangle add to 180°, so
.
Using the law of cosines,

Step-by-step explanation:
Use unitary method
Have a good day
Answer:
a.) 
Step-by-step explanation:

Find two numbers that add up to -6 and multiply to -40 (you will most likely need a negative and a positive because -40):
-10 and 4
Factor:

Finito.
Answer:
The second one
Step-by-step explanation:
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