Answer:
the answer would be 4
Step-by-step explanation:
4x2=8
8÷2=4
Step-by-step explanation:
We have xy = 28, x² + y² = 65 and x³ + y³ = 407.
Since (x + y)(x² - xy + y²) = x³ + y³,
x + y = (x³ + y³)/(x² + y² - xy)
= (407) / [(65) - (28)]
= 407 / 37
= 11.
Hence the sum of the numbers is 11.
Answer:
coefficent matrix
Step-by-step explanation:
P. 366
"If the column of constant terms is not included, the matrix reduces to that of the coefficent matrix of the system"
-1 -3 -1
9 -9 -1
-1 -3 4