How do you solve for x? (x5)(x6)=25242

2 Answers
Jan 12, 2017

x=112±1324 i.e. 4.9583 or 6.0417

Explanation:

Let x6=w and then x5=w+1. Also let a=524 and then the equation (x5)(x6)=25242 can be written as

w(w+1)=a2 or w2+wa2=0

and hence using quadratic formula b±b24ac2a

w=1±1+4×1×a22

= 12±1+4a22

As a=524,

1+4a2=1+4×25242

= 1+25122=144+25122=1312

and w=12±1324

and x=w+6=112±1324

or x=5.5±0.5417 i.e. 4.9583 or 6.0417
graph{(x-5)(x-6)-25/24^2 [4.859, 6.109, -0.255, 0.37]}

Jan 12, 2017

x=42324and6124

Explanation:

(x5)(x6)=25242

Let (x6)=a; then (x5)=a+1

Now the equation becomes

(a+1)a=24+1242=124(1+124)

a2+a124(1+124)=0

a2+(1+124)aa24124(1+124)=0

a(a+1+124)124(a+1+124)=0

(a+1+124)(a124)=0

(a+2524)(a124)=0

So a=2524anda=124

Now
when a=2524

x=a+6=2524+6=42324

Again

when a=124

x=a+6=124+6=6124