B - 3/4 = 7/10
add 3/4 to both sides to isolate the b
b = 7/10 + 3/4
b = 28/40 + 30/40
b = 58/40
b = 1 18/40
b = 1 9/20
Answer:
64
Step-by-step explanation:
64
Hope it helped!
you'd use the pythagorean theorem.
a^2+b^2=c^2
a is the first leg, b is the second leg, and c is the third leg.
10^2+13^2=c^2
100+169=c^2
269=c^2
take the square root of both sides
16.4=c
16.4cm is your answer!

check your calculator for the [!] factorial button.
also bear in mind that most calculators also have an [ₙPᵣ] button, to get Permuations, and you can just use that.