Expand and Simplify: (3/4+2a)(8a+9ba)-(5+a)(3/2a+b)

Question

(34+2a)(8a+9ba)(5+a)(32a+b)=? (\frac{3}{4}+2a)(8a+9ba)-(5+a)(\frac{3}{2}a+b)=\text{?}

Video Solution

Step-by-Step Solution

To solve this problem, we'll simplify the expression step by step using the distributive law.

Step 1: Apply the distributive property to the first part of the expression: (34+2a)(8a+9ba) (\frac{3}{4} + 2a)(8a + 9ba) .

  • Distribute 34 \frac{3}{4} to 8a 8a and 9ba 9ba : 34×8a=6a \frac{3}{4} \times 8a = 6a and 34×9ba=274ab \frac{3}{4} \times 9ba = \frac{27}{4}ab .
  • Distribute 2a 2a to 8a 8a and 9ba 9ba : 2a×8a=16a2 2a \times 8a = 16a^2 and 2a×9ba=18a2b 2a \times 9ba = 18a^2b .

The first part expands to: 6a+274ab+16a2+18a2b 6a + \frac{27}{4}ab + 16a^2 + 18a^2b .

Step 2: Apply the distributive property to the second part of the expression: (5+a)(32a+b) (5 + a)(\frac{3}{2}a + b) .

  • Distribute 5 5 to 32a \frac{3}{2}a and b b : 5×32a=152a 5 \times \frac{3}{2}a = \frac{15}{2}a and 5×b=5b 5 \times b = 5b .
  • Distribute a a to 32a \frac{3}{2}a and b b : a×32a=32a2 a \times \frac{3}{2}a = \frac{3}{2}a^2 and a×b=ab a \times b = ab .

The second part expands to: 152a+5b+32a2+ab \frac{15}{2}a + 5b + \frac{3}{2}a^2 + ab .

Step 3: Simplify the expression by subtracting the second part from the first:

  • Combine like terms: 6a152a 6a - \frac{15}{2}a and 274abab \frac{27}{4}ab - ab .
  • Subtract constants and like terms: - 6a152a=32a 6a - \frac{15}{2}a = -\frac{3}{2}a . - 274abab=274ab44ab=234ab \frac{27}{4}ab - ab = \frac{27}{4}ab - \frac{4}{4}ab = \frac{23}{4}ab . - (16a232a2)+(18a2b5b)(16a^2 - \frac{3}{2}a^2) + (18a^2b - 5b).

The full simplified expression is: 32a+234ab+(16a232a2)+(18a2b5b) -\frac{3}{2}a + \frac{23}{4}ab + \left(16a^2 - \frac{3}{2}a^2\right) + (18a^2b - 5b) .

Recognize that 16a232a2=322a232a2=292a2 16a^2 - \frac{3}{2}a^2 = \frac{32}{2}a^2 - \frac{3}{2}a^2 = \frac{29}{2}a^2 , the final answer is:

The simplified expression is: 32a+534ab+1412a2+(18a25)b -\frac{3}{2}a + 5\frac{3}{4}ab + 14\frac{1}{2}a^2 + (18a^2-5)b .

Answer

32a+534ab+1412a2+(18a25)b -\frac{3}{2}a+5\frac{3}{4}ab+14\frac{1}{2}a^2+(18a^2-5)b