Answer:
a) x=5/2 (or in decimal form 2.5)
b) k=-1/2 (or in decimal form -0.5)
c) x=3
Explanation:
a)
6-2x=4x-9
subtract 6 from both sides: 6-2x-6=4x-9-6
simplify: -2x=4x-15
subtract 4x from both sides: -2x-4x=4x-15-4x
simplify: -6x=-15
solve: x=-15/-16 (or further simplified x=5/2)
b)
10k+7=-3-10k
subtract 7 from both sides: 10k+7-7=-3-10k-7
simplfy: 10k=-10k-10
add 10k to both sides: 10k+10k=-10k-10+10k
simplify: 20k=-10
solve: k=-10/20 (or further simplified k=-1/2)
c)
4+3x=2x+7
subtract 4 from both sides: 4+3x-4=2x+7-4
simplify: 3x=2x+3
subtract 2x from both sides: 3x-2x=2x+3-2x
solve: x=3