RT = RS + ST
RT = 8x
RS = 14
ST = 4x + 6
14 + 4x + 6 = 8x
Combine like terms:
20 + 4x = 8x
Subtract 4x from both sides of the equation:
20 + 4x – 4x = 8x – 4x
20 = 4x
Divide both sides by 4 to solve for x:
20/4 = 4x/4
5 = x
Substitute x = 4 into the original equation to find the value of RT:
14 + 4x + 6 = 8x
14 + 4(5) + 6 = 8(5)
14 + 20 + 6 = 40
40 = 40
Therefore, the correct answer is D: 40