Answer:
Rule: If working with an inequality and you either mult. or div. by a negative number, you must reverse the direction of the inequality symbol.
Step-by-step explanation:
Your job here is to simplify 9t-4>32, in which the variable (t) is already positive. Here you do NOT switch signs or reverse the direction of the inequality symbol. Adding 4 to both sides, we get 9t > 36, or t > 4.
If, however, you had -9t-4>32 to work with, the situation would be different because t in this inequality is negative. Adding 4 to both sides results in:
-9t > 36. To solve for t, we must divide both sides by -9 AND reverse the direction of the inequality symbol:
t < -4.
Rule: If working with an inequality and you either mult. or div. by a negative number, you must reverse the direction of the inequality symbol.
Answer:
2x² + 9x - 5
Step-by-step explanation:
Given
(2x - 1)(x + 5)
Each term in the second factor is multiplied by each term in the first factor, that is
2x(x + 5) - 1(x + 5) ← distribute both parenthesis
= 2x² + 10x - x - 5 ← collect like terms
= 2x² + 9x - 5
Answer:
x = - 7, x = - 1
Step-by-step explanation:
To find the zeros let f(x) = 0 , that is
x² + 8x + 7 = 0
Consider the factors of the constant term (+ 7) which sum to give the coefficient of the x- term (+ 8)
The factors are + 7 and + 1 , since
7 × 1 = + 7 and 7 + 1 = + 8 , then
x² + 8x + 7 = 0
(x + 7)(x + 1) = 0 ← in factored form
Equate each factor to zero and solve for x
x + 7 = 0 ⇒ x = - 7
x + 1 = 0 ⇒ x = - 1
Answer:
A. -10
B. -1
C. 5
Step-by-step explanation:
A. 3x-4 = 3(-2)-4 = -10
B. 3x-4 = 3(1)-4 = -1
C. 3x-4 = 3(3)-4 = 5
