My math teacher isnt really clear during my math class i need a bit of help on this one.

Question

-9(-5-4c) or -9 times -5 minus 4c.

Answer 1

-9(-5-4c)= 45+36c

=-9 time (-5-4c)

the mistake is to ignore the paretheses

and calculate -9(-5)-4c = 45-4c

PEMDAS is the arithmetic order of operations

P stands for Parentheses, calculate what's inside the parentheses first

before Multiplying by what's outside the Parentheses

P=Parentheses

E=Exponents

M=Multiplication

D=Division

A=Add

S=Subtract

do the calculations in that order