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Expand and Simplify (x-1)(2x+3)

Please can someone expand and simplify this?
(x-1)(2x+3)
I got 2x^2+x-3, but it's wrong.
If it helps this is the link to the question.
https://vle.mathswatch.co.uk/images/questions/question8740.png
Thanks.

(edited 4 years ago)

Reply 1

lhh2003

Original post by DillonB07

Please can someone expand and simplify this?
(x-1)(2x+3)
I got 2x^2+x-3, but it's wrong.
Thanks.
If it helps this is the link to the question.
https://vle.mathswatch.co.uk/images/questions/question8740.png

Use FOIL

Multiply the first terms , x * 2x = 2x^2

Multiply the outermost terms , x * 3 = 3x

Multiply the inner terms , -1 * 2x = -2x

Multiply the last terms , -1 * 3 = -3

Add them all together , 2x^2 + 3x - 2x - 3 = 2x^2 + x - 3

Reply 2

DillonB07

Original post by lhh2003

This is what I put as my answer, but it said that it was wrong.

Reply 3

DillonB07

Original post by DillonB07

This is what I put as my answer, but it said that it was wrong.

I just tried again though and it was correct.
Maybe because Mathswatch is being laggy?

Reply 4

KAF128___

Original post by DillonB07

I just tried again though and it was correct.
Maybe because Mathswatch is being laggy?

Not sure. Your answer IS correct. I am seeing a few problems with people trying to get sufficient precision to satisfy MathsWatch, especially where long decimal numbers involved.