Answer:
can i see a pic
Step-by-step explanation:
<span>The axis of symmetry is x = –4.
</span><span>The domain is all real numbers.
</span><span>The x-intercepts are at (–6, 0) and (–2, 0).
</span>
I think its a) 172.50 but im not exactly sure.
18 kg of 15% copper and 72 kg of 60% copper should be combined by the metalworker to create 90 kg of 51% copper alloy.
<u>Step-by-step explanation:</u>
Let x = kg of 15% copper alloy
Let y = kg of 60% copper alloy
Since we need to create 90 kg of alloy we know:
x + y = 90
51% of 90 kg = 45.9 kg of copper
So we're interested in creating 45.9 kg of copper
We need some amount of 15% copper and some amount of 60% copper to create 45.9 kg of copper:
0.15x + 0.60y = 45.9
but
x + y = 90
x= 90 - y
substituting that value in for x
0.15(90 - y) + 0.60y = 45.9
13.5 - 0.15y + 0.60y = 45.9
0.45y = 32.4
y = 72
Substituting this y value to solve for x gives:
x + y = 90
x= 90-72
x=18
Therefore, in order to create 90kg of 51% alloy, we'd need 18 kg of 15% copper and 72 kg of 60% copper.
Answer:
4x² + 20x - 2
Step-by-step explanation:
To evaluate (c ￮ d)(x), substitute x = d(x) into c(x)
c(x² + 5x)
= 4(x² + 5x) - 2
= 4x² + 20x - 2
