<span> Compatible numbers are numbers that look nice or friendly with each other when we do mental calculation to estimate a product, but especially a division</span>
Answer:
153, 9
Step-by-step explanation:
multiply and 7 and 9
I) f(2)=1.5
ii) f(x)=0 ⇒ x=1.2
iii) k=-1
iv) x=1 ⇒ f(x)=1