Given QR is congrent to LN and QR = 4x + 2 and LN = x + 7.
So, QR = LN
Hence, we can set up an equation as following:
4x + 2 = x + 7
4x + 2 - x = x + 7 - x Subtract x from each sides.
3x + 2 = 7 By simplifying.
3x + 2 - 2 = 7 - 2 Subtract 2 from each sides.
3x = 5
Divide each sides by 3 to isolate x.
So,
![x=(5)/(3)](https://img.qammunity.org/2019/formulas/mathematics/high-school/w3l1f4qsmwmycnyocqulqlvat7c9bi8rxp.png)
Next step is to plug in
in QR = 4x+2 to get length of QR.
So,
![QR = 4((5)/(3))+2](https://img.qammunity.org/2019/formulas/mathematics/high-school/gqgt7bx24j64lgyzfmgh6x5s3mm3xk0v1f.png)
Since 2 can be written as 2/1.
By multiplying the second fraction by the common denominator 3.
By simplifying the second fraction.
![=((26)/(3))](https://img.qammunity.org/2019/formulas/mathematics/high-school/nziu7nkxy5f4guxhqbjninpoy6lvl4e21m.png)
So,
![QR=(26)/(3)](https://img.qammunity.org/2019/formulas/mathematics/high-school/s9lo2wn3m4zpsmfnaiuiyj5f78lv9at53j.png)