Answer:
Josh's parent's house in Texas is the midpoint between South Carolina and California.
Step-by-step explanation
Let distance from South Carolina to California = D
D = 2,500 miles
Let distance from South Carolina to Josh's parent's house in Texas = D1
D1 = 12x - 106
Let distance from Josh's parent's house in Texas to California = D2
D2 = 5x + 685
Solve if Josh's parent's house in Texas is the midpoint between South Carolina and California
D1 = D2 = D/2
D/2 = 2,500 miles / 2
= 1,250 miles
D1 = D2 = 1,250 miles
D1 + D2 = D
Substituting D1 = 12x-106 and
D2 = 5x+685 and
D = 2,500
D1 + D2 = D
(12x-106) + (5x+685) = 2,500
Open parenthesis
12x - 106 + 5x + 685 = 2,500
Collecting like terms
12x + 5x = 2,500 - 685 + 106
17x = 1,921
Divide both sides by 17
x = 1,921 / 17
= 113
x = 113
Substitute x into D1 and D2
D1 = 12x - 106
D1 =12(113) - 106
= 1,356 - 106
D1 = 1,250
D2 = 5x + 685
D2 = 5(113) + 685
= 565 + 685
D2 = 1,250
Therefore, Josh's parent's house in Texas is the midpoint between South Carolina and California