Ok so I assume
28 and decreased by 12.5%
percent means partst out of 100 so
12.5%=12.5/100=0.125
first find 12.5% of 28 then subtract
0.125 times 28=3.5
decrease
28-3.5=24.5
answer is 24.5
Step-by-step explanation:

Answer:
10
Step-by-step explanation:
Answer: √51
—————————
a^2 + b^2 = c^2
a^2 + 7^2 = 10^2
a^2 + 49 = 100
a^2 = 51
√(a^2) = √51
a = √51