Question

(minus 2 X + 5 Y - 3 Z)^2​

Answer 1

ANSWER:

• The value of above expression
• = 4x² + 25y² +9z² -20xy -30yz +12xz

GIVEN:

• (-2x+5y-3z)²

TO FIND:

• The value of above expression.

SOLUTION:

Formula:

(a+b+c)² = a²+b²+2ab+2bc+2ca

Now:

=(-2x+5y-3z)²

= (-2x)² +(5y)²+(-3z)² + 2(-2x)(5y) + 2(5y)(-3z) + 2(-2x)(-3z)

= 4x² + 25y² +9z² -20xy -30yz +12xz

The value of above expression:

= 4x² + 25y² +9z² -20xy -30yz +12xz

NOTE:

some important formulas:

• (a+b)² = a²+b²+2ab
• (a-b)² = a²+b²-2ab
• (a+b+c)² = a²+b²+2ab+2bc+2ca
• (a+b)² = (a-b)² +4ab
• (a-b)² = (a+b)² -4ab
• (a+b)(a-b) = a²-b²