Answer:
Choice 1
Choice 4
Choice 5
Step-by-step explanation:
For this one you just have to plug in the x in every equation and solve it. If the answer is true it's true, but if it's false it's false.
Let's solve each of these...
Number 1:
[tex]9-3x=0\\9-3(3)=0\\9-9=0\\0=0[/tex]
As you can see 0 does equal itself so this one is true.
Number 2:
[tex]3x+1=9\\3(3)+1=9\\9+1=9\\10\neq9[/tex]
10 does not equal 9 so this one would be false.
Number 3:
[tex]5x-7=1\\5(3)-7=1\\15-7=1\\8\neq1[/tex]
This one is also false.
Number 4:
[tex]2x+4=10\\2(3)+4=10\\6+4=10\\10=10[/tex]
This one is true.
Number 5:
[tex]\frac{x}{3}+5=6\\\frac{(3)}{3}+5=6\\1+5=6\\6=6[/tex]
This one is true.
Number 6:
[tex]\frac{9}{x}-1=4\\\frac{9}{(3)}-1=4\\3-1=4\\2\neq4[/tex]
This one is false.
