I'll mark as brainliest if you get the correct answer WITH step by step explaination.
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ANSWER:
value of "a" is: a= -b√3+7+4√3
value of "b" is: [tex]\frac{-a\sqrt{3}+7\sqrt{3} }{y} +4[/tex]
STEP-BY-STEP EXPLANATION:
1. (rationalize the denominator)
(2 + √3) × (2 + √3) =a + b√3
2. (write the repeated multiplication in exponential form)
(2 + √3)² =a + b√3
3. (use (a + b)² = a² + 2ab + b² to expand the expression)
4 + 4√3 + 3 = a + b√3
4. ( add the numbers)
7 + 4√3 = a + b√3
5. (move the variable to the left-hand side and change its sign. then, move the constants to the right-hand side and change their signs)
6. (change the signs on both sides of the equation)
a = -b√3 + 7 + 4√3
1. (rationalize the denominator. then, use the commutative property to reorder the terms)
(2 + [tex]\sqrt{3}[/tex]) × (2 + [tex]\sqrt{3}[/tex] ) = a + b[tex]\sqrt{3}[/tex] → (2 + [tex]\sqrt{3}[/tex]) × (2 +[tex]\sqrt{3}[/tex] ) = a + [tex]\sqrt{3}[/tex]b
2. (write the repeated multiplication in exponential form)
(2 + √3)² =a + [tex]\sqrt{3}[/tex]b
3. (use (a + b)² = a² + 2ab + b² to expand the expression)
4 + 4[tex]\sqrt{3}[/tex] + 3 = a + [tex]\sqrt{3}[/tex]b
4. (add the numbers)
7 + 4 [tex]\sqrt{3}[/tex] = a + [tex]\sqrt{3}[/tex]b
5. (move the expression to the left-hand side and change its sign. then, move the constants to the right-hand side and change their signs)
- [tex]\sqrt{3}[/tex]b + 7 + 4 [tex]\sqrt{3}[/tex] = a → -[tex]\sqrt{3}[/tex]b = a - 7 - 4[tex]\sqrt{3}[/tex]
6. (divide both sides of the equation by [tex]-\sqrt{3}[/tex])
b = [tex]- \frac{a}{\sqrt{3} } + \frac{7}{\sqrt{3}} + 4[/tex]
7. (rationalize the denominator)
b = [tex]b=-\frac{a\sqrt{3} }{\s3}} +\frac{7\sqrt{3} }{{3} } +4[/tex]
8. (write all numerators above the common denominator)
b = [tex]\frac{-a\sqrt{3}+7\sqrt{3} }{y} +4[/tex]
there you go! I hope this helped. goodluck! :)