No it’s not linear. To be linear it has to form a straight line.
Y=2x^3 is nonlinear, since it's a cube equation. y=x+5 is linear, because it's a line with y intercept (0,-5) and slope 1. y=\sqrt(x-5) is nonlinear, because it's a quadratic equation when reversing x and y. 5x+5y=25 is equal to x+y=5 ot y=-x+5, which is also linear. y=x^2/2 is a quadratic equation, so it's nonlinear.
.7 repeating would make it 7/9
Answer:
⇒ The given quadratic equation is x2−kx+9=0, comparing it with ax2+bx+c=0
∴ We get, a=1b=−k,c=9
⇒ It is given that roots are real and distinct.
∴ b2−4ac>0
⇒ (−k)2−4(1)(9)>0
⇒ k2−36>0
⇒ k2>36
⇒ k>6 or k<−6
∴ We can see values of k given in question are correct.
2.5cm=25 mm
2.9cm=29 mm
3.1cm=31 mm
They give it in cm because it’s easier to guess how long it will be in real life