Question

daca x supra 4 egal y supra 7 , atunci 9x-2y supra x+3y egal

Answer 1

x/4=y/7=k

x=4k
y=7k

(9x-2y)/(x+3y)=  (9*4k-2*7k)/(4k+3*7k)=

=(36k-14k)/(4k+21k)=

= 22k/25k=  22/25

Answer 2

[tex] \frac{x}{4} = \frac{y}{7} \to \frac{x-y}{4-7} \\ Proportii \text{ } derivate \\ x=4 \\ -y=-7 \to I-yI=I-7I \to \boxed{y=7} \\ ------------------ \\ 9x-2y=9*4-2*7=36-14=22 \\ x+3y=4+3*7=4+21=25 \\ \boxed{\boxed{Raspuns: \frac{22}{25} }} [/tex]