5-7[-3+-7]=75? How is that? i would think it to be -12...please help.
2007-08-21 07:39:16 · 9 answers · asked by pondbilly 2 in Science & Mathematics ➔ Mathematics
PEMDAS method:
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction
5 - 7 * (-3 + -7) = ? first do the parenthesis
>>5 - 7 * (-10) = ? subtract -7 from -3 to get -10.
>>5 - (-70) = ? multiply 7 and -10 to get -70.
>>5 + 70 = 75 Subtracting a negative is the same as adding a positive. 5 + 70 = 75
2007-08-21 07:49:14 · answer #1 · answered by Toledo Engineer 6 · 0⤊ 0⤋
the -7 is multiplying the -10 = 70. Adding 5 = 75.
2007-08-21 07:45:49 · answer #2 · answered by John V 6 · 0⤊ 0⤋
Hi,
Perhaps there's something missing here, but it looks as if you have an identity, and your task is to covernt the left side to 75. Do it this way:
5-7(-3+-7) = 75
5-7(-10) = 75 (Do the operations inside the paretheses first.)
5+70 = 75 ( negative * negative = positive)
75 = 75
Hope this helps.
FE
2007-08-21 07:57:08 · answer #3 · answered by formeng 6 · 0⤊ 0⤋
Brackets, Exponents, Multiplication/Division, Addition/Subtratiom
5-7(-3+-7)=75 Brackets First
5-7(-3-7)=75
5-7(-10)=75 Then multiply by the number in front of the brackets. A negative times a negative is a postiive so you get +70
5+70=75
75=75
The rest is simple.
2007-08-21 07:45:36 · answer #4 · answered by wyzard_2001 3 · 0⤊ 0⤋
5-7[-3+-7]=75
do parentheses first
5 - 7 * (-10) = 75
then multiply
5 - (-70) =75
with a negatives u add the opposite
5 + 70 = 75
then u have your answer
75=75
2007-08-21 07:52:49 · answer #5 · answered by quennofda***world 2 · 0⤊ 0⤋
5-7[-3+-7]=75
Parentheses first, so
5-7[-10]=75
Multiplication next
5+70=75
Addition next
75=75
Minus times minus is plus. Right?
2007-08-21 07:49:37 · answer #6 · answered by pampam 2 · 0⤊ 0⤋
pemdas means order of operations
do parenthesis, exponenents, multiplication, division, addition then subraction
So parenthesis [-3+-7] = [-10]
then multiple -7[-10] = 70
then add 5 = 75
2007-08-21 07:47:19 · answer #7 · answered by b_ney26 3 · 0⤊ 0⤋
5 - 7(-3 + -7)
= 5 - 7(-10)
= 5 + 70
= 75
Must do PEMDAS
Parentheses
Exponents (none in this case)
Multiplication
Division (none in this case)
Addition
Subtraction (none in this case)
2007-08-21 07:46:40 · answer #8 · answered by Mathematica 7 · 0⤊ 0⤋
do whats in the brackets first
-3+-7= -10
multiply by -7
70
add the 5
75
2007-08-21 07:46:48 · answer #9 · answered by britbutt 3 · 0⤊ 0⤋