When the sum of a number and -5 is multiplied by -7, the result us 49.

\(-5(x+(-7)]=49\\ -5x + 35 = 49\\ -5x = 14\\ x = -\dfrac{14}{5}\)

When the sum of a number and -5 is multiplied by -7, the result us 49.

How do you eat an elephant?  One bite at a time. 

Take this problem apart and look at one bite at a time.

"When the sum of a number and –5 is..."       What does this mean?  First, there's a number.  We don't know what it is so let's let X stand for it. So the sum of X and –5 is simply X +(–5), or X–5.  Put some parentheses around that, like this: (X–5)

What is the next part of the problem?  "...is multiplied by –7"  so let's write out that multiplication: (X–5)(–7)

The problem says that that equals 49, so put it all together           (X–5)(–7) = 49

Then just multiply the left side and the equation looks like this:       –7X + 35 = 49

Subtract 35 from both sides                                                              –7X = 14

Divide both sides by –7                                                                         X = –2 

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Sum of a number and -5    ====   (x+-5)

    is multiplied by  -7        ======  7(x-5)

       the result is 49      =========== -7(x-5) = 49    use distributive property

                                                            -7x + 35 = 49    subtract 35 from both sides of the equation

                                                             -  7x = 14        divide both sides by -7

                                                                 x = -2 

Step 1: Simplify both sides of the equation.

−5(x−7)=49

(−5)(x)+(−5)(−7)=49(Distribute)

−5x+35=49

Step 2: Subtract 35 from both sides.

−5x+35−35=49−35

−5x=14

 Step 3: Divide both sides by -5.

\(\frac{-5x}{-5}=\frac{14}{-5}\)

x= -14/5

answer is x=-14/5     

Big Brother, where does the problem say to multiply anything by –5 ?