If the sum of the squares of nonnegative real numbers a, b, and c is 39, and ab + bc + ca = 21, then what is the sum of a, b, and c?

Step-by-step explanation:

a² + b² + c² = 39

ab + bc + ca = 21

(a + b + c)² = a² + b² +c² + 2[ab + bc +ca]

(a + b + c)² = 39 + 2*21

                 = 39 + 42

(a+ b + c)² = 81

a +b + c = √81 = √9*9

a + b + c = 9

i can't solve unless i know what the line is

step-by-step explanation:

welcome to/p>

26 is 33.33% of 78

step-by-step explanation:

26 is what percent of 78?

26 is p% of 78

equation: y = p% * x

solving our equation for p

p% = y/x

p% = 26/78

p = 0.3333

convert decimal to percent:

p% = 0.3333 * 100 = 33.33%