Answer:
3 - (-7)
= 3 + 7.
Step-by-step explanation:
A double negative is equivalent to a plus.
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
(5x+15)(6x-10)
= 30x^2 + 30x - 50x - 150
= 30x^2 - 20x - 150
No solution
because delta ( b^2 - 4ac ) is lower than 0(zero) .