Finding Solutions with Trial and Error

You are given a value for x within an equation and told that you need to work out the answer by trial and improvement. What is the first thing you do?

• Try to remember formulas that might help

• Multiply x by six different numbers

• Make an intelligent guess at the value of x

• Move on to the next question

Tags

CCSS.8.EE.C.7B

After you have made an intelligent guess at the value of x what do you do next?

• Assume that you guessed correctly

• Guess another value for x

• Guess another three values for x

• Put your guessed value into the equation in place of x

After you have put your guessed value into the equation in place of x what do you do next?

• Work out the equation using your guessed value

• Look at your friend’s note and copy the results

• Wait for the teacher doing it all for you

• Do nothing till the end of the tedious class :)

Tags

CCSS.HSF.IF.A.2

When you work out the equation using your guessed value, you find that your value is too high so what do you do next?

• Make another guess that is higher than your first

• Make another guess that is lower than your first

• Make three more guesses that are higher

• Make three more guesses that are lower

You are told that Louise has some sisters and, within an equation, the number of sisters she has is represented by x. What would be a good first guess for the value of x?

• 1

• 2

• 10

• 20

Tags

CCSS.7.EE.B.4A

Within an equation, the boiling point of a solution is represented by x. What would be a good first guess for the value of x?

• 50 degrees C

• 75 degrees C

• 100 degrees C

• 200 degrees C

You are told that the value of x lies somewhere between 300 and 400, and you are given an equation containing x. What would be a good first guess for x?

• 301

• 302

• 350

• 399

x² + x³ = 80, what is the value of x?

• 2

• 3

• 4

• 5

x³ - 2x = 115, what is the value of x?

• 3

• 5

• 7

• 9

Tags

CCSS.8.EE.A.2

x² + 4x + 7 = 14x - 9, which of the following is a possible value of x?

• 3

• 4

• 6

• 8

Tags

CCSS.HSA-REI.B.4B