For the first one c-9=(2)(4)+6 You are gonna multiply 2 and 4 first, 2*4=8. Now you have c-9=8+6. 8+6=14. So now the equation is c-9=14. Now we are going to add 9 to both sides. So c=23 For the second equation 10+y=90. We are going to subtract 10 from both sides. So, y=80. Third, add 4 to both sides. a=10. Fourth, subtract 8 from both sides. d=-9 Fifth, 5+2(3+4)=-x. First we are going to add 3 and 4. 3+4=7. 5+2(7)=-x. Next we are going to multiply 2 and 7. 2*7=14. 5+14=-x. 5+14=19. So our equation is 19=-x. Next we are going to multiply both sides by -1. Making our final equation x=-19. c=23 y=80 a=10 d=-9 x=-19 I hope that helps, if you need any further explanation just ask.<span />