If $α$ and $β$ are the roots of $2 x^{2} + 2 x - 40 = 0$ , find $α \cdot β$ .

Practise more Number and Algebra.

Free questions with an explanation for every one, and full timed HKDSE (Hong Kong) mock tests.

All Number and Algebra questions Take a mock test

More Number and Algebra questions

Simplify $\frac{( 3 x ^{2} y ^{- 3} ) ^{2}}{9 x y ^{2}}$ and express your answer with positive indices.
The marked price of a watch is increased by $20%$ and then sold at a discount of $25%$ . What is the overall percentage change in the price…
Solve the simultaneous equations ${2 x + 3 y = 7 3 x - 2 y = 4$ . What is the value of $x + y$ ?
In an arithmetic sequence, the 4th term is $14$ and the 8th term is $30$ . Find the sum of the first $10$ terms of this sequence.
Solve the linear inequality $2 (x - 3) \leq 5 x + 3$ .
The sum to infinity of a convergent geometric series is $16$ , and the second term is $3$ . What are the possible values of the common ratio…