Math 2 Lesson: 34 – 8
1.1. Knowledge to remember
1.2. Math forms
Form 1: Calculate
– Set alignment.
– Perform subtraction in turn from right to left, when the unit row of the number being subtracted is not enough to subtract, you need to perform the subtraction with memory.
Form 2: Build the math and find the result.
– Write calculations according to the data of the given problem.
– Perform calculations to find the value of the result.
Form 3: Find x
To find the unknown term, subtract the known term from the sum.
To find the number to be subtracted, we take the difference plus the minus number.
1.3. Solving Textbook Exercises
Perform the subtraction in order from right to left.
Set the calculation and then calculate the difference, knowing the subtracted and subtracted numbers are:
a) 64 and 6; b) 84 and 8; c) 94 and 9.
– Set calculation: Write the calculation so that the digits are in the same row and column together.
– Calculation: Subtract numbers from right to left in turn.
Ha’s family has 34 chickens, Ly’s family has 9 chickens less than Ha’s family. How many chickens does Ly keep at home?
To find out how many chickens Ly’s family raised, we subtract 9 chickens from Ha’s family.
The number of chickens in Ly’s house is
34 – 9 = 25 (chicken)
Answer: 25 chickens.
a) x + 7 = 34
b) x – 14 = 36.
– To find a term, we subtract the other term from the sum.
– To find the number to be subtracted, we take the difference plus the minus number.
a) x + 7 = 34
x = 34 – 7
x = 27
b) x – 14 = 36
x = 36 + 14
x = 50