Answer: - 235
<u>Step-by-step explanation:</u>
f(x) = -3x² + 13x + 3
f(-7) = -3(-7)² + 13(-7) + 3
= -3(49) - 91 + 3
= -147 - 88
= -235
You need 3 trucks of sand that hold 5 tons and 2 trucks that hold 3 tons to move all the sand in one trip
Rule needed: i^2 = -1
Standard form a + bi
(3 + 2i)(7 - 5i) FOIL
3 * 7 = 21
3 * - 5i = - 15i
2i * 7 = 14i
2i * -5i = - 10i^2 = - 10 * -1 = 10
Putting it all back together.
31 - i