Answer:
i) 28 - 30i
ii) 36 + 28i
Step-by-step explanation:
i) x = 6 + i ⇒2x = 2(6 + i) = 12 + 2i
z = 4 - 8i ⇒ 4z = 4(4 - 8i) = 16 - 32i
2x + 4z = (12 + 2i) + (16 - 32i) = 28 - 30i
ii) w = -1 + 5i and z = 4 - 8i
w × z = (-1 + 5i)(4 - 8i) = -4 + 8i + 20i - 40
⇒collect like terms
w × z = -4 + 28i - 40
∵ 
∴w × z = -4 + 28i - 40(-1) = -4 + 28i + 40 = 36 + 28i
Answer:
17.7
Step-by-step explanation:
This figure is a pentagon - a shape with 5 sides. In a pentagon, the figure's angles add to 540.
100 + 7x-4 + 3x + 23 + 9x - 6 + 90 = 540
190 +19x + 13 = 540
203 + 19x = 540
19x = 337
x = 17.7
$2.89 Just do the cost divided by the gallons and round up.
She has more than enough because with 8 cups you only need 2 quarts. She has 3 which gives her 12 cups.
Answer:
25.5 mph
Step-by-step explanation:
So Bradley's speed can be modeled by the equation y=2x+40 where y=speed, x=time in hours after noon, and b=initial speed
So 12:15 is 15 minutes after noon, which is also 0.25 or 1/4 of an hour after noon. This is the x-value. Plug this into the equation to get his speed at 12:15
y=2(0.25)+40
y=0.5+40
y=40.5
So his speed was 40.5 at the time and since he was going 15 miles over the speed limit, the speed limit is 15 less than his speed
40.5 - 15 = 25.5
