So in math class we are doing Simplifying Algebraic Expressions or at least that is what the lesson is called but what is 7x +7. I was just wondering because it is a step in my question and im not sure if i could just add them normally or not.

No you can’t add them, but you can do this: 7x+7 =0
-7 -7
7=7x
/7 /7
1=x

No, you can’t because, to simply algebraic expressions the numbers or letters or coefficients need to be the same. 7x have a number with a letter but, the +7 only have the number. In other words, the letters and/or the exponents (in this one there’s no exponent but I’m just putting an example) need to be the same in order to combine them

Answer d; a supplementary angle = 180°, so if that angle = 150°, y would = 30°.