Question

If 2ab + 5cd = 5 and abcd = 1, what is the value of 4a²b ²+ 25c²d²

Answer 1

Answer:

Find the value of 4a²b²+25c²d² if 2ab+5cd=5 and abcd=1. ... ( 2ab+5cd)^2 = 4a^2b^2 +25c^2d^2 +20abcd. 5 ^2 

Answer 2

Answer:

4a²b² + 25c²d² = 5

Step-by-step explanation:

Let's start with squaring both sides of the first equation:

(2ab + 5cd)² = 5²

4a²b² + 20abcd + 25c²d² = 25

Since abcd = 1, make the substitution and simplify:

4a²b² + 20(1) + 25c²d² = 25

4a²b² + 20 + 25c²d² = 25

Subtract 20 from both sides:

4a²b² + 25c²d² = 5