4X=Y and X-87=Y

Solve one of them for X, substitute that solution into the other equation and solve, or just substitute your choices in to find a match, in this case it’d be 29, plug 29 back in for X to find that Y=116

#2) same thing

C=T+60 and C*2/3=T

follow the same procedure as the first one, and the answer is 120

#3)pratice makes perfect

B+17=G and B+G=431

the math in this one is even simplier than #2, no dirty fractions. just swamp B+17 in for G on the 2nd one and you get 2B +17=431, move the 17 and 2B=414, divide both sides by 2….B=207, but this time we also need the other variable, so plug 207 back into the first on for B this time, add the 17 and G=224. You can verify by plugging both B & G back into the second equation, and sure enough 224 + 207 = 431

#4)

W-18=S and W=S*2.5

substitute S for (W-18) in the 2nd equation. W=(w-18)*2.5 Distribute the 2.5 so W=2.5W-(18*2.5) or W=2.5W – 45 add that 45 to both sides so W+45=2.5W, subtract a W from both sides 45=1.5W, and divide both sides by 1.5 and you get W=30, plug that back in to the top and S =12

4x = x+87

3x + 87; solve for x.

x=29

2. Let x=trapeze artist

x-60=2/3x

solve for x

3. x=number of boys; x+17 = girls

x+x+17=431

solve for x.

4. x = Southern State

2.5x = x+18

1.5x = 18

solve for x