With any parallelogram, the diagonals bisect each other. This is another way of saying that they cut each other in half.
FH is one diagonal that is split into two equal pieces by the other diagonal EG.
The two parts of FH (KH and KF) are congruent to each other, so KH = KF. They combine back to FH
By the segment addition postulate
KH + KF = FH
KH + KH = FH .... KF has been replaced with KH (works because KF = KH)
2*KH = FH
Now use substitution
2*KH = FH
2*15 = FH .... replace KH with 15 (since KH = 15)
2*15 = 4x-2 ... replace FH with 4x-2 (since FH = 4x-2)
and solve for x
2*15 = 4x-2
30 = 4x-2
30+2 = 4x-2+2 ... add 2 to both sides
32 = 4x
4x = 32
4x/4 = 32/4 ... divide both sides by 4
x = 8
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Answer: x = 8
The minimum cost option can be obtained simply by multiplying the number of ordered printers by the cost of one printer and adding the costs of both types of printers. Considering the options:
69 x 237 + 51 x 122 = 22,575
40 x 237 + 80 x 122 = 19,240
51 x 237 + 69 x 122 = 20,505
80 x 237 + 40 x 122 = 23,840
Therefore, the lowest cost option is to buy 40 of printer A and 80 of printer B
The equation, x + 2y ≤ 1600 is satisfied only by options:
x = 400; y = 600
x = 1600
Substituting these into the profit equation:
14(400) + 22(600) - 900 = 17,900
14(1600) + 22(0) - 900 = 21,500
Therefore, the option (1,600 , 0) will produce greatest profit.