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put this solution on YOUR website!#17.
Let x = the weight of Tweedledum and y = the weight of Tweedledee.
According to Tweedledum:
1)
According to Tweedledee:
2)
Now we have a system of equations with two unknowns and this system can be solve for x and for y.
We'll use the elimination method so we multiply equation 1) by 2:
1a)
Now we'll subtract equation 2) from equation 1a) to eliminate the y
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Divide both sides by 3.
So Tweedledum weighs 120 lbs.
Now back to equation 1) where we substitute x = 120 and solve for y.
Simplify.
Subtract 240 from both sides.
Tweedledee weighs 121 lbs.
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#18
Let C = the number of miniature cycles and S = the number of bumper stickers.
1) C + S = 5,000 The sum of the cycles and stickers is 5,000
2) ($0.63)C + ($0.52)S = $2,798.00
Here we can use the substitution metod to solve this system of equations.
Rewrite equation 1) as:
1a) C = 5,000-S and substitute this for C in equation 2)
2a) 0.63(5000-S)+(0.52)S = 2,798 Simplify and solve for S
3150-0.63S+0.52S = 2,798 Simplify.
3150-0.11S = 2,798 Subtract 3150 from both sides.
-0.11S = -352 Divide both sides by -0.11
S = 3,200 This is the number of bumper stickers.
C = 5,000-3200
C = 1,800 This is the number of miniature cycles.
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#20
Let R = the number of rabbits and P = the number of pheasants.
Since both rabbits and pheasants have but one head each, then:
1) R+P = 35
Rabbits have four legs each while pheasants have two legs each, so we can write the total number of legs as:
2) 4R+2P = 94
Rewrite equation 1) as:
1a) R = 35-P Now multiply this equation by 4 to get:
1b) 4R = 140-4p and substitute this for 4R in equation 2, then solve for P.
2a) 140-4P+2P = 94 Simplify.
140-2P = 94 Subtract 140 from both sides.
-2P = -46 Divide both sides by -2.
P = 23 There are 23 pheasants.
R = 35-P
R = 35-23
R = 12 There are 12 rabbits.
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