Exercise

Solve the following simultaneous equations.

$3 a+5 b=26 ; a+5 b=22$

Solve using formula

$5m^2-4m-2=0$

Solve using formula.

$x^2+6x+5=0$

Decide whether following sequence is an $\mathrm{A}.\mathrm{P}.$, if so find the $20\mathrm{th}$ term of the progression.

$-12,-5,2,9,16,23,30,.....$

Is $127, 132, 137...$ an $\mathrm{A}.\mathrm{P}.$ if so then find the common difference.

The sum of father's age and twice the age of his son is $70 .$ If we double the age of the father and add it to the age of his son the sum is $95 .$ Find their present ages.

Complete the following.

In figure, chord $\mathrm{EF}\parallel$ chord $\mathrm{GH}$. Prove that, chord $\mathrm{EG}\cong$ chord $\mathrm{FH}$. Fill in the blanks and write the proof.

Proof: Draw $\mathrm{seg} \mathrm{GF}$.

$\angle \mathrm{EFG}=\angle \mathrm{FGH}$ _____ $\left(\mathrm{I}\right)$

$\angle \mathrm{EFG}=$_____ inscribed angle theorem$\left(\mathrm{II}\right)$

$\angle \mathrm{FGH}=$_____ inscribed angle theorem$\left(\mathrm{III}\right)$

$\therefore \mathrm{m}(arc\mathrm{EG})=$_____ from $\left(\mathrm{I}\right), \left(\mathrm{II}\right), \left(\mathrm{III}\right).$

chord $\mathrm{EG}\cong$ chord $\mathrm{FH}$_____.