Answer:
D. 5 units
Step-by-step explanation:
The parallel segments divide the slant segments proportionally:
7.5/10.5 = x/7
x = 7(7.5/10.5) = 5 . . . . . multiply by 7
The value of x is 5 units.
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If you want to use corresponding sides of similar triangles, you get the same result. ΔIGH ~ ΔIJK
IJ/IG = IK/IH
7/(7+10.5) = x/(x+7.5) . . . . substitute shown values
7(x +7.5) = 17.5x . . . . . . . cross multiply
7(7.5) = 10.5x . . . . . . . . . subtract 7x
x = 7(7.5/10.5) = 5 . . . . . divide by the coefficient of x