Answer:
4. b) [tex]4x^2-20xy+25y^2[/tex]
5. b) [tex]x^2+14x+49[/tex]
Step-by-step explanation:
4. [tex](2x-5y)^2[/tex]
First, one must rewrite the exponential equation as a multiplication problem,
[tex](2x-5y)(2x-5y)[/tex]
Now distribute, multiply every term in one of the parenthesis by every term in the other parenthesis,
[tex]=(2x-5y)(2x-5y)\\\\=(2x)(2x)+(2x)(-5y)+(-5y)(2x)+(-5y)(-5y)[/tex]
Now simplify the given expression,
[tex]=(2x)(2x)+(2x)(-5y)+(-5y)(2x)+(-5y)(-5y)\\\\=4x^2-10xy-10xy+25y^2[/tex]
Combine like terms,
[tex]=4x^2-20xy+25y^2[/tex]
5.[tex](x+7)^2[/tex]
To solve this problem, one should follow the same series of steps as they did to solve the last expression. First, rewrite the exponential expression as a multiplication problem.
[tex](x+7)(x+7)[/tex]
Now distribute, multiply every term in one of the parenthesis by every term in the other parenthesis,
[tex]=(x)(x)+(7)(x)+(7)(x)+(7)(7)[/tex]
Simplify the expression,
[tex]=(x)(x)+(7)(x)+(7)(x)+(7)(7)\\\\=x^2 + 7x + 7x + 49[/tex]
Finally, combine like terms,
[tex]=x^2+14x+49[/tex]
