Simplify 9i(2+3i):
9i×2=18i
9i×3i=27i
18i+27i
Answer:
f(-2) = -2
Step-by-step explanation:
f(-2) means find the y value when x = -2
The y value when x = -2 is-2
f(-2) = -2
Answer: A
Explanation: The zeroes of f(x) are the value/s of x such that f(x) = 0. So, we need to find the values of x in the equation f(x) = 0.
Note that
f(x) = 0
⇔ x² + 3x - 10 = 0
By factoring into binomials, x² + 3x - 10 = (x + 5)(x - 2). Thus,
x² + 3x - 10 = 0
⇔ (x + 5)(x - 2) = 0
⇔ x + 5 = 0 or x - 2 = 0
⇔ x = -5 or x = 2
Hence, the zeroes of x are -5 and 2.
Answer:
B
Step-by-step explanation:
Answer:
11
Step-by-step explanation:
Let the no. of helmet be x
cost of 1 helmet = $12.00
cost of x helmet = $12.00*x = $12x
Let the no. of tire pumps be y
cost of 1 tire pumps = $8.00
cost of x tire pumps = $8.00*y = $8y
Given that total no. of helmet and pump is 18
thus
x + y = 18
y = 18-x
also given
total money spent is $188
thus
12x+8y = 188
using y = 18 - x
we have
12x + 8(18-x) = 188
=> 12x+ 144 - 8x = 188
=> 4x = 188-144 = 44
=> x = 44/4 = 11
Thus, no of helmet bought by Margo is 11.
