Question

Is 9 X square + 25 y square is equal to 181 and xy is equal to minus 6 find the value of 3 X + 5y

Answer 1

Answer:

{3x+5y}^2=9x^2+2.3.5.xy+25y^2

=(42-23}^2

then 3x+5y = (42-23)

Answer 2

Step-by-step explanation:

Given:−

❒ 9x² + 25y² = 181

❒ xy = -6

Find:−

❒ Value of (3x + 5y)

Solution:−

we, have

⇁9x² + 25y² = 181 〘Given〙

Taking L.H.S

↦9x² + 25y² = (3x)² + (5y)²

➠(3x + 5y)²

★using {(a + b)}^{2} = {a}^{2} + 2ab + {b}^{2}

➠(3x)² + 2(3x)(5y) + (5y)²

➠9x² + 30xy + 25y²

★Rearranging The Term★

➠9x² + 25y² + 30xy

★ using 9x^{2} + 25 y^{2} = 181

➠181 + 30xy

★now, using xy = - 6

➠181 + 30(-6)

➠181 + (-180)

➠181 - 180

➠1

⇨3x + 5y = 1

Hence, answer is 1