Need asap will mark brainliest/ i don’t understand

answer choices:

a. 5
b. 6
c. 7
d. 8

Find the solution(s) to x^2-14+49=0

Evaluate each expression. determine if the final simplified form of the expression is positive or negative -42 (-4)2 42

Long division setup showing an incomplete calculation. 12 is in the divisor, 6839 is in the dividend, and 5 hundreds and 6 tens is written in the quotient. 6000 is subtracted from 6839 to give 839. an unknown value represented by a box is being subtracted from 839. what number should be placed in the box to complete the division calculation?