Answer:
E = 8
Step-by-step explanation:
y - x = 4
y - (3y) = 4
y - 3y = 4
2y = 4
y = 4/2
y = 2
x = 3y
x = 3×2
x = 6
x + y = 2+6
x+y = 8
Answer:
3 : 5
Step-by-step explanation:
Since there are 3 boys, the number of girls is 5.
Causing the ratio to be 3 : 5
Let's start by writing a system of linear equations:
c -> cookies
cb -> candy bars
(You can use any abbreviations to your preference)
Abby:
4 cookies
3 candy bars
$10.25 per bag
The equation would be:
4c+ 3cb = $10.25
Marissa:
2 cookies
7 candy bars
$14.75 per bag
The equation would be:
2c + 7cb = $14.75
So our linear equation system would be:
<span>4c+ 3cb = $10.25
</span><span>2c + 7cb = $14.75
I would try to get rid of one variable so I can solve for the other variable. In this case, it is easier to get rid of c since I can multiply the second equations by 2. Then it would subtract the two equations.
(2c + 7cb = $14.75) 2 = 4c + 14 cb = $29.50
4c + 3cb = $10.25
- 4c+14 cb = $29.50 (4c would get canceled.)
---------------------------------
-11 cb = - $19.25 (Divide by -11 to solve for cb)
</span> --------- -------------
-11 -11
cb = $1.75
Now we know cb (candy bar) cost, we would substitute this value into cb into one of the equations. It doesn't matter which equation you put it in. I will substitute it in the first equations.
4c + 3 (1.75) = $10.25
4c + 5.25 = $10.25 (Multiply 3 by 1.75)
-5.25 -5.25 (Subtract 5.25 on both sides)
4c = 5 (Divide by 4 on both sides to get c)
---- ---
4 4
c= 1.25
Check the work:
4(1.25) + 3(1.75)
= $10.25
2(1.25) + 7(1.75)
= $14.75
Total cost:
cookies = $1.25
candy bars = $ 1.75
Hope this helps! :)
Ok so for number 5, AB is proportional to BC just like PQ is proportional to QR. AB = 9, BC = 15, PQ = 3, and QR = x. 9/15 = 3/x. Cross Multiply: This gives you - 9x = 45. Divide both sides by 9, and you get x = 5. QR = 5
Answer:
48
Step-by-step explanation:
100/50 = 2
This means each question was worth 2%
96% / 2% = 48
She got 48 questions right
