Jake spent a total of 70 cents.
b = black-and-white = 8 cents
c = color = 15 cents
70 = 8b + 15c
he made a total of 7 copies
b + c = 7
system of equation:
70 = 8b + 15c
b + c = 7
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b + c = 7
b + c (-c) = 7 (-c)
b = 7 - c
plug in 7 - c for b
70 = 8(7 - c) + 15c
Distribute the 8 to both 7 and - c (distributive property)
70 = 56 - 8c + 15c
Simplify like terms
70 = 56 - 8c + 15c
70 = 56 + 7c
Isolate the c, do the opposite of PEMDAS: Subtract 56 from both sides
70 (-56) = 56 (-56) + 7c
14 = 7c
divide 7 from both sides to isolate the c
14 = 7c
14/7 = 7c/7
c = 14/7
c = 2
c = 2
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Now that you know what c equals (c = 2), plug in 2 for c in one of the equations.
b + c = 7
c = 2
<em>b + (2) = 7
</em><em />Find b by isolating it. subtract 2 from both sides
b + 2 = 7
b + 2 (-2) = 7 (-2)
b = 7 - 2
b = 5
Jake made 5 black-and-white copies, and 2 color copies
hope this helps
Answer:
Step-by-step explanation:
30 kg - 4.3 kg = 25.7 kg
25.7 kg - 0.4 kg = 25.3 kg
25.3/2.3 = 11
There are 11 student books in the box.
Answer:
(-2,1)
Step-by-step explanation:
Since this is an upwards opening parabola, the minimum point is at the vertex
We can find the x coordinate of the vertex by
y = 2x^2 +8x +9
where a=2 b =8 and c =9
x = -b/2a
x = -8/(2*2)
= -8/4 = -2
The x coordinate is -2
Now substitute this in to find the y coordinate
y = 2(-2)^2 +8(-2)+9
= 2*4 -16+9
8-16+9
=1
The vertex = (-2,1), which is the minimum point
3.7
I hope this helps! Negatives cancel out negatives
The answer is B because they are alternating exterior angles
