question_answer 18)

Simplify the expressions and find the value if \[x\]is equal to 2. (i) \[x+7+4(x-5)\]             (ii) \[3(x+2)+5x-7\]          (iii) \[6x+5(x-2)\]              (iv) \[4(2x-1)+3x+11\]

Answer:

                (i) \[x+7+4(x-5)=x+7+4x-20\] \[=x+4x+7-20\]                                                 \[\left| \text{rearranging terms} \right.\] \[=5x-13=5(2)-13\] \[=10-13=-3.\]                 (ii) \[3(x+2)+5x-7=3x+6+5x-7\]                 \[=3x+5x+6-7\]                                                 \[\left| \text{rearranging terms} \right.\]                 \[=8x-1=8(2)-1\] \[=16-1=15.\]                 (iii) \[6x+5(x-2)=6x+5x-10\]                 \[=11x-10=11(2)-10\]                 \[=22-10=12.\]                 (iv)  \[4(2x-1)+3x+11=8x-4+3x+11\]                 \[=8x+3x+11-4\]                                               \[\left| \text{rearranging terms} \right.\]                 \[=11x+7=11(2)+7\] \[=22+7=29\].