Use letters to stand for unknown numbers, and learn to build and simplify algebraic expressions from real situations.
A letter-number (variable) can represent an unknown quantity. Word phrases translate into algebraic expressions by identifying the operation being described.
Munirathnam has some marbles. If he doubles them and adds 5, write this as an expression using m for his marbles.
2m + 5
A rectangle's length is 3 more than its width w. Write an expression for the length.
w + 3
Terms with the same letter-number part can be combined by adding or subtracting their coefficients, just like combining similar objects when counting.
Simplify: 4x + 3x
7x
Simplify: 5y + 2 − 2y + 3
(5y − 2y) + (2+3) = 3y + 5
1. A number n is tripled and then 7 is subtracted. Write this as an expression.
2. A box has b balls. If 4 more boxes with the same number are added, write an expression for the total.
3. Simplify: 6a + 4 − 2a + 1
4. Simplify: 8p − 3p + 5
5. Ramesh's age is r. In 5 years, his age will be what expression?