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Question 104094: Hello out there,I need some help with some tough problems,the first one is,Mr.Adams buys a bag of apples and a bag of pears for a total of $14.00.There are eight pounds of fruit in all.The apples cost $1.50 per pound,and the pears cost $2.30 per pound.How many pounds of pears did he buy?The second one is,Which of the following points are solutions to:x+2y<-12 and 3x-y>-2 (-1,-5),(0,0),or(1,-7).The next one is,Solve the system of equations by substitution:y=x^2+2x-2 and y=3x+4.And the last one is,Use elimination to solve 6x-y/4=-9 and 3x+2y=-30.Thanks to whoever can help.
Answer by edjones(8007)   (Show Source):
You can put this solution on YOUR website! A)
Let a=lbs of apples, p=lbs of pears
.
1.5a+2.3p=14
a+p=8
.
a=8-p
1.5(8-p)+2.3p=14
12-1.5p+2.3p=14
.8p=2
p=2.5 lbs
a=5.5 lbs
Check:
2.5*2.3+1.5*5.5=14
B)
by substitution (1,-7) is the only correct answer.
.
C)
x^2+2x-2=3x+4
x^2-x-6=0
(x-3)(x+2)=0
x=3, x=-2
.
D)
6x-y/4=-9
3x+2y=-30
.
24x-y=-36
3x+2y=-30
.
the rest is like the 1st problem.
I'll leave that up to you.
.
Ed
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