Are my answers correct? PLZ HELP ME!

8.Expand the following expressions & simplify where possible:
a. 3(4a+7)
= 12a + 21
b. -3(x-7) - 2x(4y+1)
= 21+-5x+-8xy

9. Solve the following equations:
a. 14e-11= -25
= e=-1
b. 9-7a= 2
= a=1
c. x^2-3= 118
=x^2= 121 x= {-11,11}

10. Factorise each of the following by taking out the highest common factor:
a. 5x-15
= 5(-3+x)
b. 2a-3ab
= a(2+-3b)
c. 12ab-30ac+15a^2b
= 3a (4b+-10c+5ab)

i need to know if my answers are right please! thank you! 10 points! :D xoxo

8
b. =21-5x-8xy
You don't write +- as they multiply and comes out as -

10
a. 5(x-3)
b. a(2-3b)
c. 3a(4b-10c+5ab)

All other are correct. Good job

yes they are

yes they are all correct. question 11: how do magnets work?