All you have to do is add 125 by 75 and you get 200. Now you have to subtract 500 by 200 which is 300 and here you go your answer is 300. The bookstore has to sell 300 more books in order to sell 500 books by friday
It’s 34. hope this helps xx
We can use linear combinations of the equations to eliminate variables.
3x - 4y = 1
-2x + 3y = 1
To eliminate y we'll make the linear combination of 3 times the first equation minus four times the second.
9x - 12y = 3
-8x + 12y = 4
Adding,
x = 7
We could solve for y directly but let's use another linear combination, twice the first plus three times the second:
2(3x - 4y) + 3(-2x + 3y)= 2(1)+3(1)
y = 5
Check: 3(7)-4(5)=1 good. -2(7)+3(5)=1 good.
Q18 Answer: (7,5)
y = -3x + 5
5x - 4y = -3
4y +1(5x - 4y) = 4(-3x + 5) + 1(-3)
5x = -12x + 20 -3
17 x = 17
x = 1
y = -3(1) + 5 = 2
Check: 5(1) - 4(2) = -3 good
Q19 Answer (1,2)
6x + 5y = 25
x = 2y + 24
6x = 12y + 144
5y = 25 - 12y - 144
17y = -119
y = -119/17= -7
x = 2y+24= 10
Check: 6(10)+5(-7)=25 good 2y+24=2(-7)+24=10=x good
Q20 Answer (10,-7)
3x + y = 18
-7x + 3y = -10
9x + 3y = 54
9x - -7x = 54 - -10
16x = 64
x=4
y = 18 -3x = 18-12=6
Check: 3(4)+6=18 good, -7(4)+3(6)=-10 good
Q21 Answer: (4,6)
Answer:
2 : 7
Step-by-step explanation:
6 : 21 (6 for 6 days and 21 days in 3 weeks)
2 : 7 (Simplify by dividing by 3)
<span>Sheila can ride her bicycle 6000 meters in 15 minutes.
Forming that into a ratio, that will be 6000 : 15
Doing the proportion for 2 minutes.
6000 : 15 = X : 2
Doing the computation.
6000 / 15 = X / 2
15X = 2 * 6000
15X = 12000
X = 800
So Sheila covered a total of 800 meters in 2 minutes.</span>