Answer:
+
Step-by-step explanation:
++ = +
+- = -
-+ = -
-- = +
Example:
-1 x -1 = 1
1 x -1 = -1
Answer:
x = - 2, x = 7
Step-by-step explanation:
Given
f(x) = 4x² - 20x - 56
To find the zeros let f(x) = 0, that is
4x² - 20x - 56 = 0 ( divide through by 4 )
x² - 5x - 14 = 0 ← in standard form
(x - 7)(x + 2) = 0 ← in factored form
Equate each factor to zero and solve for x
x + 2 = 0 ⇒ x = - 2
x - 7 = 0 ⇒ x = 7
9 dived by 3 = 3
so he surfed for 3 hours = 1/3 of 9
and there are 6 hours left
so he spent 6 hours building a sandcastle
