Answer:
B. y = 1.5x +8
Step-by-step explanation:
You can try x=4 in the various equations to see which gives the right value (14).
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A: y = -8(4) +1.5 = -30.5
B: y = 1.5(4) +8 = 14 . . . . . . . . . this equation works
C: y = 8(4) +1.5 = 33.5
D: y = -1.5(4) +8 = 2
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Alternatively, you can use the 2-point form of the equation of a line to write the equation:
y = (y2 -y1)/(x2 -x1)(x -x1) +y1
y = (20 -14)/(8 -4)(x -4) +14 . . . . fill in (x1, y1) = (4, 14); (x2, y2) = (8, 20)
y = 1.5(x -4) +14 . . . . . simplify somewhat
y = 1.5x +8 . . . . . . . . write in slope-intercept form
Factor the equation using difference of squares, which says that a^2-2ab+b^2=(a-b)^2.
a is 2 since the square root of 4 is 2 and b is 5 because the square root of 25 is 5.
Final answer: (2x-5y)^2
30cm cubed the formula is v=bh
