Presentation on theme: "1-1 Variables and Expressions variable- a letter that stands for a number *In Algebra we will write products involving variables without the multiplication."— Presentation transcript:
1-1 Variables and Expressions variable- a letter that stands for a number *In Algebra we will write products involving variables without the multiplication symbol Ex. 5t means 5 t 12y means 12 y * Be sure to always write the variable second
Numerical Expression - Two or more numbers combined with operations signs (there is no equals sign) Ex Variable Expression- An expression with one or more variables Ex. 3ym r
4 + 8 y + 2 5y w m x Drag each expression to the correct box Variable Numerical
Write a variable expression for each word phrase. 1.) Nine more than a number y 2.) 4 less than a number n 3.) A number z times 3 4.) 8 more than 5 times a number t 5.) A number q divided by 7
1.) Vicki and Tamra are working on their math homework together. Vicki has worked p problems and Tamra has worked 4 times as many as Vicki. Write an expression to show how many problems they have worked altogether. Write an expression for each 2.) Frank had 3b baseball cards and his brother had b baseball cards. They combined their cards, and then gave away 2b cards. Write an expression to shows how many they have left.
1-3 Variables and Expressions To evaluate a variable expression, replace each variable with the given number. Use proper the proper order of operations. Evaluate when x = -5 and y = 6 1.) 3x2.) xy 3.) 12 + x + y4.) 4y +9
5.) 12 6.) 6(x+y) y 7.) 3y2 + 2x8.) 2x+3y 7 Evaluate when x = 5 and y = 6