Answer to problem 1:
x=2
Reasoning:
1) Simplify 10/20 to 1/2
2) Multiply the numerator and denominator by 2 to get 2/4
Answer to problem 4:
1 in: 18 in
Reasoning:
1) Convert 15 feet to inches
15*12=180
2) Use a ratio of 10 inches to 180 in and simplify it to 1:18
Answer to problem 5:
m = 38.44
1) Use the technique "Cross multiplication" and make the following equation
8.45*7.5=3.6m
2) 8.45*7.5=138.375
3) 138.375=3.6m and divide 3.6 from both sides of the equation,
4) You get 38.4375, and round up to the nearest hundredth of 38.44
Answer to problem 6:
92°
When 2 triangles are similar, their lengths are needed to multiplied by a scale factor but, the angles remain the same.
Sorry, I didn't have enough time to answer the other question...
Hope this helped...