Answer: 4x^2+16x-2
Explanation:
You need to use BEDMAS order. (Brackets, exponents, division & multiplication left to right, addition & subtraction left to right)
Since there is nothing else you can do to the brackets, leave it for now.
There is also nothing you can do to the exponents, since you can't square a variable you don't know the value of.
Now, we do division & multiplication (there is no division in this case)
2x(3x + 4)−2x^2+8x-2 (start with the underlined section, using distributive property)
6x^2+8x−2x^2+8x-2
Now, since this is not an equation (no equal sign) but an expression, we just need to combine like terms.
6x^2+8x−2x^2+8x-2 (start with the x^2 terms. 6-2=4, so we end up with 4x^2)
4x^2+8x+8x-2 (now move on to the x terms. 8+8=16, so we end up with 16x)
4x^2+16x-2
And we're done! No more like terms to combine!