Remember P,E,M,A and that division is a special
case of multiplication and that subtraction is a
special case of addition.
First we have P, for parentheses:
(-8)² + 42/[18-(6+5)] <--- do the innermost parentheses that has something to
do inside it first. There is nothing to do in
the parentheses (-8). So the first innermost
parentheses that has something to do inside it is
(6+5), so we replace (6+5) by 11. Copy everything
else over.
(-8)² + 42/[18-11] <--- do the innermost parentheses that has something to
do inside it, which is to replace [18-11]) by 7.
Copy everything else over.
(-8)² + 42/7 <--- there are no more parentheses with anything to do
inside them, so next of PEMA comes E for
exponents. We have one exponent, (-8)² which is
64, so we replace (-8)² by 64. Copy everything
else over.
64 + 42/7 <--- there are no more exponents, so the next letter of
PEMA is M for multiplication and we must remember
that division is a special case of multiplication,
so the first multiplication is really a division,
a special case of multiplication, so we replace
42/7 by 6. Copy everything else over:
64 + 6 <--- there are no more multiplications or
divisions. The last letter of PEMA is A for
addition, [If we had any subtractions, we remember
that subtraction is a special case of addition, but
we don't have any subtractions]. So we just do this
last addition
70 <--- final answer.
Edwin