Question

c) Determinati necunoscuta:
150 - {2 x [(a - 9): 8 – 3] + 9 x 7} x 2 = 8. Mi-e mi-a dat 65 dar nu cred dacă e bine. Va rog încercați!?!? ​

Answer 1

Răspuns:

$150 - [2 * [(a - 9): 8-3] + 9*7] * 2 = 8\\\\150 = 8 + [2 * [(a - 9): 8-3] + 9*7] * 2\\\\150 -8= [2 * [(a - 9): 8-3] + 9*7] * 2 \\\\142 =[2 * [(a - 9): 8-3] + 63] * 2 \:\:\:\:\: /:2\\\\ 71 = 2 * [(a - 9): 8-3] + 63 \\\\71-63 = 2 * [(a - 9): 8-3]\\\\ 8 = 2 * [(a - 9): 8-3]\:\:\:\:\: /:2\\\\ 4 = (a - 9): 8-3\\\\4+3 = (a - 9): 8\\\\7 = (a - 9): 8\:\:\:\:\: /*8\\\\56 = a-9\\\\56+9=a\\\\\boxed{a=65}$