I need help on question 3

For what values of the variable x is the expression square root of 7x+14+ square root of 7-x a real number?

Someone answer asap for ! the following statements are true about the coins calvin and sasha have collected. * calvin and sasha has the same amount of money. * calvin has only quarters. * sasha has dimes, nickels, and pennies * calvin has the same number of quarters as sasha has dimes. * sasha has $1.95 in coins that are not dimes. exactly how many quarters does calvin have?

Which value of m will create a system of parallel lines with no solution? y = mx - 6 8x - 4y = 12