Pre-algebra home work

[avtom]

when a number is next to a variable in an expression like 8y + 5 (5 X 5) is that the same as 8 X y

 

[JeffM]

when a number is next to a variable in an expression like 8y + 5 (5 X 5) is that the same as 8 X y

Yes "8y" means "8 times y", but stop using X to mean multiplication in anything to do with algebra. You will get it confused with x and X used as unknowns or variables. 8 * y is another way to show multiplication.

 

[mmm4444bot]

Jeff is correct. We call the product 8y "implied multiplication" because there is no multiplication sign.

8(y) is also implied multiplication.

 

[Deleted member 4993]

Just to confuse the issue:

62 ? 6*10 + 2

6½ ? 6 + ½

 

[Denis]

lest ye forget: DO NOT show the variable first, like y8 to represent y * 8; ALWAYS 8y or 8(y) or 8*y

And remember that the old multiplication and division symbols have been changed to * and / respectively.

 

[mmm4444bot]

6½ ? 6 + ½

Mixed numbers are "implied addition".

Can't remember ever seeing or hearing that phrase before, but it's true.

 

[mmm4444bot]

the old multiplication and division symbols have been changed to * and / respectively

With some exceptions (of course!)

It's fairly standard to continue using the old multiplication symbol in scientific notation (not a pre-algebra topic).

\(\displaystyle 3.14159 \times 10^{18}\)

Also, compound fractions are sometimes written with the old division sign.

\(\displaystyle \frac{1}{5} \div \frac{4}{7} \; \text{instead of} \; \frac{\frac{1}{5}}{\frac{4}{7}}\)