Please use an equation and show work! Thanks very much

Find three consecutive numbers such that the sum of one-fourth the first and one-fifth the second is five less than one-seventh the third

Sanderson is having trouble with his assignment. his shown work is as follows: − 3 7 7 3 = − 3 7 × 7 3 = − 21 21 = −1 however, his answer does not match the answer that his teacher gives him. complete the description of sanderson's mistake. find the correct answer.

3a + 5b - 7 = 0 a - 2b - 4 = 0 solve the system by the elimination method. check your work {(96/11, -5/11)} {(34/11, -5/11)} {(32/33, 5/11)}