A)
Equation: RS + ST = RT
(2x + 10) + (x-4) = 21
Solve:
2x+10 + x-4 = 21
Combine like terms:
3x + 6 = 21
Subtract 6 from each side:
3x = 15
Divide both sides by 3:
X = 15/3
X = 5
Now replace x with 5 in each equation:
RS = 2x+10 = 2(5) +10 = 10+10 = 20
ST = x-4 = 5-4 = 1
B)
Equation: RS + ST = RT
(3x - 16) + (4x-8) = 60
Solve:
3x-16 + 4x-8 = 60
Combine like terms:
7x - 24 = 60
Add 24 to both sides:
7x = 84
Divide both sides by 7:
x = 84/7
X = 12
RS = 3x-16 = 3(12) - 16 = 36-16 = 20
ST = 4x -8 = 4(12) -8 = 48 - 8 = 40
C)
Equation: RS + ST = RT
2x-8 + 11 = x+10
Solve:
2x-8 + 11 = x +10
Simplify left side:
2x +3 = x+10
Subtract 3 from both sides:
2x = x +7
Subtract 1x from each side:
x = 7
RS = 2x -8 = 2(7) - 8 = 14-8 = 6
RT = x+10 = 7+10 = 17
