I need help ! will mark brainliest!! :)

Step-by-step explanation:

From the Pythagorean Theorem we know

h^2=a^2+b^2 (where h is the hypotenuse of a right triangle and a and b are its legs)

In this case the single tick marks on the legs indicate they are the same length then

h^2=a^2+b^2 becomes

h^2=2a^2, and a=7 so

h^2=2(7^2)

h=7(2^(1/2))

h=9.9

x=9.9 (to nearest tenth)

the answer is a

step-by-step explanation:

because if you put 1 in to the square root of x it equals 300.