What is the answer to this problem? ignore the work. what is the correct answer?

Hello from MrBillDoesMath!

c= 42.5

Discussion:

In the attachment, L is the longest side of the right triangle and "c" is its hypotenuse. The Pythagorean theorem gives

20^2 + L^2 = c^2                     =>   as 20^2 = 400 and c = L+5

400+ L^2 = (L+5)^2                  =>  (L+5)^2 = L^2 + 10L + 25

400 + L^2 = L^2 + 10L + 24     =>  subtract L^2 from both sides

400   =  10L + 25                      =>   subtract 25 from both sides

400 -25 = 10L          =>

375 = 10L                 =>

L = 375/1- = 37.5

Hence c =  L + 5 = 37.5 +5 = 42.5

Thank you,

MrB

step-by-step explanation:

the largest number of the four options is 1.8 x 10-2

you have it in scientific notation.

1.80 x 10-6   = 0.00000180

1.80 x 10-4   = 0.000180 (bigger, or "less small", than the former one)

so

1.8 x 10-2       = 0.0180. as you see. the "less small", or the biggest one of them all.

as you have negative exponent, it means you are dividing 1.8 by 100 (i.e. moving the dot towards left, two times).

if you had positive exponent for the scientific notation, power of tenths, you would be multiplying times 100 (moving the dot towards right) as below:

1.8 x (10)2 = 180

so. if you have negative exponent in scientific notation, move the dot toward left. if it is positive, toward right as many times the exponent tells you.