If log (5x+20)=3, what is the value of x?

Question

solomonzelman · Answer

$\normalsize\color{blue}{   \log(5x+20)=3  }$

$\normalsize\color{blue}{   \log(5x+20)=3 \times \log 10  }$

$\normalsize\color{blue}{   \log(5x+20)= \log 10^3  }$

$\normalsize\color{blue}{   \log(5x+20)= \log 1000  }$

solomonzelman · Answer

can you finish it ?

anonymous · Answer

no im kinda confused I thought when you had addition it turns into a product

solomonzelman · Answer

I am just giving you the fastest approach...

anonymous · Answer

so what do I do after?

solomonzelman · Answer

If  $\normalsize\color{blue}{   \log a= \log b  }$   then   $\normalsize\color{blue}{   a= b  }$

anonymous · Answer

doesn't make any sense 
a)-19/5
b)-17/5
c)196
d)204

anonymous · Answer

@SolomonZelman

solomonzelman · Answer

this what doesn't make sense, how can you ask questions about factoring (algebra 1) and about logarithms (trigonometry) at the same time ?

anonymous · Answer

ib mathematics

anonymous · Answer

x=196 (:

anonymous · Answer

thankyou

anonymous · Answer

$$\log (5x+20)=3,$$ means 
$$5x+20=10^3$$

anonymous · Answer

they say the  same thing exactly 
that you can solve for $x$ without much trouble

solomonzelman · Answer

I forgot to use just that relation -:(

anonymous · Answer

$$5x+20=1000\
5x=980\
x=196$$