Write a two-column proof.

Question

Given: 7y=8x-14; y=6

 

Prove: x=7

 

 

I need help making a two-column proof with the statements and the reasons, please! Thank you! ( This is what I have so far)

 

 

Statements             | Reasons

                             |

1. 7y=8x-14;y=6    |   Given

                             |

2. 7(6)=8x-14        |    Substitution

                             |

3.  42=8x-14          |????

                             |

4. ???                     |???

                             |

5. x=7                   |????

 

 

(I just stopped at 5 for right, that's not the exact steps I think the two-column proof actually has)

 

Thank you again for whoever helps me! Be Blessed

 

 

Answer 1

You're doing fine so far; you just need to keep going to isolate x

Your next step is to add 14 to both sides:

42 + 14 = 8x - 14 + 14

56 = 8x

 

The final step is to divide both sides by 8:

56 / 8 = 8x / 8

7 = x

 

And just to show that the x-value is true:

7 * 6 = 8 * 7 - 14

42 = 56 - 14

42 = 42