Simplify the expression: -4x + 8 + 7x - 10
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Brady has a 20 year fixed rate mortgage for $215,500 with monthly payments of 1,305.89.the annual interest rate is 4%. what is the total cost of the principal and interest for this loan rounded to the nearest dollar

An office supply company conducted a survey before marketing a new paper shredder designed for home use. in the survey, 80 % of the people who tried the shredder were satisfied with it. because of this high satisfaction rate, the company decided to market the new shredder. assume that 80 % of all people are satisfied with this shredder. during a certain month, 100 customers bought this shredder. find the probability that of these 100 customers, the number who are satisfied is 69 or fewer.

Prove sin2a + cos2a - 1 / sin2a + cos2a + 1 = 1 - tana / 1 + cota