Answer:
![(5x + 6y^4)(5x - 6y^4)](https://img.qammunity.org/2021/formulas/mathematics/high-school/sdmmpvgdoa9pmehg8ztiiflnwcj99n9rug.png)
Explanation:
Given the expression:
![25x^2 -36y^8](https://img.qammunity.org/2021/formulas/mathematics/high-school/mjs2p6omuwrez67o6imm1vo3wjrb3ob69b.png)
We are to express it as difference of two square (u+v)(u-v). According to the rule:
![u^2 - v^2 = (u+v)(u-v)](https://img.qammunity.org/2021/formulas/mathematics/high-school/i0o95nopr6myxvacl6eb2cx9ir3ho9xzsi.png)
We need to express
as difference of squares and this is as shown:
![= 25x^2 -36y^8\\= 5^2x^2 - 6^2(y^4)^2\\= (5x)^2 -(6y^4)^2\\](https://img.qammunity.org/2021/formulas/mathematics/high-school/rxl65h258qesk0i2cunle1w71h42eqc523.png)
From the resulting expression we can say:
![u = 5x \ and \ v = 6y^4](https://img.qammunity.org/2021/formulas/mathematics/high-school/uj2k28ze9gqdg8kzlf15rwy81dcgnzrns2.png)
If we substitute in the rule above we will have:
![= (5x)^2 -(6y^4)^2\\= (5x + 6y^4)(5x - 6y^4)](https://img.qammunity.org/2021/formulas/mathematics/high-school/vcjt2mm53stfsisxvhs6pcxj2pj60fxr49.png)
Hence the expression expressed as difference of two square is:
![(5x + 6y^4)(5x - 6y^4)](https://img.qammunity.org/2021/formulas/mathematics/high-school/sdmmpvgdoa9pmehg8ztiiflnwcj99n9rug.png)