乘以以下内容：
问题1.(5x + 3)by(7x + 2)
解决方案：
To find the product of (5x + 3) (7x+2) [use distributive property]
⇒ (5x + 3) (7x + 2)
⇒ 5x(7x+2) + 3(7x+2)
⇒ (5x × 7x + 5x × 2) + (3 × 7x + 3 × 2)
⇒ 35x2 + 10x + 21x + 6
⇒ 35x2 + 31x + 6
The required answer is 35x2 + 31x + 6
问题2.(2x + 8)，由(x – 3)
解决方案：
To find the product of (2x + 8) (x – 3) [use distributive property]
⇒ (2x+8) (x – 3)
⇒ 2x (x – 3) + 8 (x – 3)
⇒ (2x × x – 2x × 3) + (8 × x – 8 × 3)
⇒ (2x2 – 6x) + (8x – 24)
⇒ 2x2 + 2x -24
The required answer is 2x2 + 2x -24
问题3.(7x + y)，乘(x + 5y)
解决方案：
To find the product of (7x + y) (x + 5y) [ use distributive property ]
⇒ 7x (x + 5y) + y (x + 5y)
⇒ (7x × x + 7x × 5y) + (y × x + y × 5y)
⇒ (7x2 + 35xy) + (xy + 5y2)
⇒ 7x2 + 36xy + 5y2
The required answer is 7x2 + 36xy + 5y2
问题4.(a – 1)乘(0.1a 2 + 3)
解决方案：
To find the product of (a – 1) (0.1a2 + 3) [use distributive property]
⇒ a (0.1a2 + 3) -1(0.1a2 +3)
⇒ 0.1a3 +3a – 0.1a2 – 3
⇒ 0.1a3 – 0.1a2 +3a – 3
The required answer is 0.1a3 – 0.1a2 + 3a – 3
问题5.(3x 2 + y 2 )by(2x 2 + 3y 2 )
解决方案：
To find the product of (3x2 + y2) (2x2 + 3y2) [use distributive property]
⇒ 3x2(2x2 + 3y2) + y2(2x2+3y2)
⇒ 6x4 + 9x2y2 + 2x2y2 + 3y4
⇒ 6x4 + 11x2y2 + 3y4
The required answer is 6x4 + 11x2y2 + 3y4
问题6.(3 / 5x + 1 / 2y)by(5 / 6x + 4y)
解决方案：
To find the product of (3/5x +1/2y) (5/6x + 4y) [ use distributive property ]
⇒ 3/5x(5/6x + 4y) + 1/2y(5/6x + 4y)
⇒ (3/5x × 5/6x + 3/5x × 4y) + (1/2y × 5/6x + 1/2y × 4y)
⇒ 1/2x2 + 12/5xy + 5/12xy + 2y2
⇒ 1/2x2 + 169/60 xy + 2y2
The required answer is 1/2x2 + 169/60xy + 2y2
问题7.(x 6 – y 6 )乘(x 2 + y 2 )
解决方案：
To find the product of (x6 – y6) (x2 + y2) [ use distributive property ]
⇒ x6 (x2 + y2) – y6(x2 + y2)
⇒ x8 + x6y2 – y6x2 – y8
The required answer is x8 + x6y2 – y6x2 – y8
问题8.(x 2 + y 2 )by(3a + 2b)
解决方案：
To find the product of (x2+y2) (3a + 2b) [use distributive property]
⇒ x2(3a + 2b) + y2(3a + 2b)
⇒ 3ax2 + 2bx2 + 3ay2 + 2by2
The required answer is 3ax2 + 2bx2 + 3ay2 + 2by2
问题9. [-3d +(-7f)]乘(5d + f)
解决方案：
To find the product of [-3d + (-7f)] (5d + f) [ use distributive property ]
⇒ (-3d) (5d + f) + (-7f) (5d + f)
⇒ (-15d2) + (-3df) + (-35fd) + (-7f2)
⇒ -15d2 -3df -35df -7f2
⇒ -15d2 – 38df – 7f2
The required answer is -15d2 – 38df -7f2
问题10.(0.8a – 0.5b)除以(1.5a – 3b)
解决方案：
To find the product of (0.8a – 0.5b) (1.5a – 3b) [use distributive property]
⇒ 0.8a( 1.5a -3b) – 0.5b(1.5a – 3b)
⇒ 1.2a2 – 2.4ab – 0.75ab + 1.5b2
⇒ 1.2a2 + 1.5b2 – 3.15ab
The required answer is 1.2a2 + 1.5b2 – 3.15ab
问题11.(2x 2 y 2 – 5xy 2 )乘(x 2 – y 2 )
解决方案：
To find the product of (2x2y2 – 5xy2) (x2 – y2) [use distributive property]
⇒ 2x2y2 (x2 – y2) -5xy2 (x2 – y2)
⇒ 2x4y2 – 2x2y4 -5x3y2 + 5xy4
The required answer is 2x4y2 – 2x2y4 – 5x3y2 + 5xy4
问题12(X / 7 + X 2/2)(2/5 + 9X / 4)
解决方案：
To find the product of (x/7 + x2/2) (2/5 + 9x/4) [use distributive property]
⇒ x/7(2/5 + 9x/4) + x2/2(2/5 + 9x/4)
⇒ 2x/35 + 9x2/28 + x2/5 + 9x3/8
⇒ 2x/35 + (9/28 + 1/5)x2 + 9x3/8
⇒ 2x/35 + (45+28/140) x2 + 9x3/8
⇒ 2x/35 + 73/140x2 + 9x3/8
The required answer is 2x/35 + 73/140x2 + 9x3/8
问题13(-a / 7 + 2/9)中的(b / 2 – B 2/3)
解决方案：
To find the product of (-a/7 + a2/9) by (b/2 – b2/3) [ use distributive property ]
⇒ (-a/7) (b/2 -b2/3) + a2/9 (b/2 – b2/3)
⇒ -ab/14 + ab2/21 + a2b/18 – a2b2/27
The required answer is -ab/14 + ab2/21 + a2b/18 – a2b2/27
问题14.(3x 2 y – 5xy 2 )乘(1 / 5x 2 + 1 / 3y 2 )
解决方案：
To find the product of (3x2y -5xy2) (1/5x2 + 1/3y2) [ use distributive property ]
⇒ 3x2y(1/5x2 + 1/3y2) -5xy2(1/5x2 + 1/3y2)
⇒ 3/5x4y + x2y3 – x3y2 -5/3xy4
The required answer is 3/5x4y + x2y3 – x3y2 -5/3xy4
问题15(2x 2 – 1)乘(4x 3 + 5x 2 )
解决方案：
To find the product of (2x2 – 1) (4x3 + 5x2) [use distributive property]
⇒ 2x2 (4x3 + 5x2 ) -1(4x3 + 5x2)
⇒ 8x5 + 10x4 – 4x3 – 5x2
The required answer is 8x5 + 10x4 – 4x3 – 5x2
问题16.(2xy + 3y 2 )by(3y 2 – 2)
解决方案：
To find the product of (2xy + 3y2) (3y2 – 2) [ use distributive property ]
⇒ 2xy (3y2 – 2) + 3y2 (3y2 – 2)
⇒ 6xy3 – 4xy + 9y4 – 6y2
The required answer is 6xy3 – 4xy + 9y4 – 6y2