Here is the formula: b•h/2
Selection B is appropriate.
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The signs of the coefficients tell you the binomial factors must have both signs positive (selections B and C only). Selection B produces an x-term that is 15x+15x=30x (as we want); selection C produces an x-term that is 45x+5x=50x (not what we want).
Q3-Q1=IQR is the formula.
500 is one tenth as much as 50 is correct.
500 of 1/10=50
<span>500 is 10 times as much as 50 is wrong.
</span>500 x 10= 5,000 not 50