R + b = 21
2b = r
now we sub eq 2 into eq 1
r + b = 21
2b + b = 21
3b = 21
b = 21/3
b = 7
2b = r
2(7) = r
14 = r
so there are 7 bluejays (b) and 14 robins (r)...for a total of 21
Answer:
Do (8, -9) times 5 for both numbers
Step-by-step explanation:
You are buying 2 items so let's use two different variables to represent each:
p = number of tubes of paint
b = number of disposable brushes
cost = price per item × number of items
Equations from information given:
4p + 0.50b = 20 ← from the first 2 sentences
2p = b ← if there are twice as many brushes as paint tubes you need 2 times paint tubes to equal number of brushes
Solve the problem by using substitution... 1b equals 2p so replace b with that:
4p + 0.50(2p) = 20
4p + 1p = 20 ← 0.50 is half so half of 2p is 1p
5p = 20 ← combine like terms
p = 4 ← divide both sides of the equation by 5
Recall the equation 2p = b replace p with 4
2(4) = b
8 = b
ANSWER:
You purchased 4 tubes of paint and 8 disposable brushes.
Answer: (b) A
<u>Step-by-step explanation:</u>
A: the center of the circle
B: the diameter of the circle
C: the radius of the circle
D: <em>not sure, could be the perimeter</em>
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Circles are named by their center, so this is named "Circle A".
At the moment it’s in standard form. We can easily turn this into slope int form (y= mx + b) tho
3y= -18x -18
y= -6x - 6