Class 10

Math

All topics

Quadratic Equations

From 2012-2016, the amount (in crores) spent on natural gas N and electricity E by Indian residents can be described by the following expressions, where t is the number of years since 2012.

Gas spending model,

N = $2.13t_{2}−4.21t+37.40$

Electricity spending model,

E = $−0.209t_{2}+5.393t+307.735$

What is the total amount A spent on natural gas and electricity by Indian residents from 2012 to 2016?

- $1.467t_{2}+7.423+121.721$
- $1.339t_{2}−8.729t+76.245$
- $1.01t_{2}+7.083+97.83$
- $1.921t_{2}+1.183t+345.135$

$E=−0.209t_{2}+5.393t+307.735$ (Electricity speeding models)

So, total $=E+N$

So, total $=(2.13t_{2}−4.21t+37.40)+(−0.209t_{2}+5.393t+307.735)$

Total $=1.921t_{2}+1.183t+345.135$