Search 72,569 tutors
FIND TUTORS
Ask a question
0 0

math help please

solve for y. 3x-6y+12=0
  number two
solve for x. |x -2|+5=3
number three
| 8-5x | + 2+4
number four
| 3x - 7 |= | 3x +7 |
  number five
The perimeter of a rectangle is 88inches. if the length of the rectangle is eight inches more than three times the width, find the dimensions.
    number six
Barney invested $80,000 in two investment. the first part was invested at 3% interest and the remainder was invested at 4% interest. the total interest he received at the end of one year was 3,000. How much money was invest at 3%?
  
  number seven
How many pounds of candy worth 50cent per pound and how many pounds of peanuts worth 90 cent per pound must be mixed to get a mixture of 64 pound worth 60 cent per pound.
 is it A) 16 lbs. .nuts and 48lbs. candy   (b)48 lbs nuts and 16 lbs.candy  (c)32 lbs..nuts and 32lbs candy (d) 8lbs.nuts and 56lbs.candy
   thank you as you help
Tutors, please sign in to answer this question.

1 Answer

3x-6y+12=0
3x+12=6y
(3x/6)+12/6=y
(x/2)+2=y
 
lx-2l+5=3
lx-2l=-2
no solution because absolute value can never be negative
 
I'll assume you mean l8-5xl+2=4
8-5x+2=4
10-5x=4
-5x=-6
x=6/5
also, 5x-8+2=4
        5x-6=4
        5x=10
          x=2
 
l3x-7l=l3x+7l
case 1: 3x-7=3x+7, -7=7, no solution
case 2:  3x-7=-3x-7, 6x=0, x=0
case 3:  -3x+7=3x+7, -6x=0, x=0
case 4:  -3x+7=-3x-7, 7=-7, no solution
 
w=width
3w+8=length
P=2l+2w
88=2(3w+8)+2w
88=6w+16+2w
88=8w+16
72=8w
w=9 inches
3*9+8=27+8=35
l=35 inches
check: 88=35+35+9+9=70+18=88
 
I=prt
3000=3%x+4%(80,000-x)
3000=0.03x+0.04(80,000-x)
3000=0.03x+3200-0.04x
3000=-0.01x+3200
-200=-0.01x
200=0.01x
$20,000=x (invested at 3%)
$80,000-$20,000=$60,000 invested at 4%
 
50x+90(64-x)=64(60)
50x+5760-90x=3840
-40x+5760=3840
-40x=-1920
40x=1920
x=48 lbs of candy and 64-48=16 lbs of nuts; A) is the answer
 
 

Comments

You're very welcome.
Arthur D.

Woodbridge college algebra tutors