Sagot :
Answer:
y<−3 or y>7
Step-by-step explanation:
y2−4y−21>0
y2−4y−21=0
(y+3)(y−7)=0
y+3=0 or y−7=0
y=−3 or y=7
y<−3
−3<y<7
y>7
Answer:
y<−3 or y>7
Step-by-step explanation:
y2−4y−21>0
y2−4y−21=0
(y+3)(y−7)=0
y+3=0 or y−7=0
y=−3 or y=7
y<−3
−3<y<7
y>7