Answer:
The values of a and b are a = 11 , b = 7
Step-by-step explanation:
* Lets explain how to solve the problem
* In the exponential functions we have some rules
1- In multiplication if they have same base we add the power
# Ex: b^m × b^n = b^(m + n) ⇒ b is the base , m and n are the powers
2- In division if they have same base we subtract the power
# Ex: b^m ÷ b^n = b^(m – n) ⇒ b is the base , m and n are the powers
3- If we have power over power we multiply them
# Ex: (b^m)^n = b^(mn) ⇒ b is the base , m and n are the powers
* Lets solve the problem
∵ The equation is [tex](5x^{7}y^{2})(-4x^{4}y^{5})=-20x^{a}y^{2}[/tex] ⇒ (1)
- At first multiply the coefficients
∵ -4 × 5 = -20
- Multiply the base x
∵ [tex](x^{7})(x^{4})=x^{7+4}=x^{11}[/tex]
- Multiply the base y
∵ [tex](y^{2})(y^{5})=y^{2+5}=y^{7}[/tex]
∴ [tex](5x^{7}y^{2})(-4x^{4}y^{5})=-20x^{11}y^{7}[/tex] ⇒ (2)
- By comparing (1) and (2)
∴ a = 11 and b = 7
* The values of a and b are a = 11 , b = 7
