The value of B-A is -6x²-xy+15y² .
A statement where the algebraic expressions are equated with an equal sign with each other is called an Equation.
It is given that
A = 5x²+3xy-7y²
B = -x²+2xy+8y²
To calculate is B - A
B- A = ² (-x²+2xy+8y²) - (5x²+3xy-7y² )
B-A = -x²+2xy+8y² - 5x²- 3xy +7y²
B-A = -6x²-xy+15y²
Therefore the value of B-A is -6x²-xy+15y² .
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