哪两个数之和为 19,差为 5?
引入了一个系统来定义从负无穷到正无穷的数字。该系统被称为数字系统。数系很容易在数轴上表示,整数、整数、自然数都可以在数轴上定义。数轴包含正数、负数和零。
方程是一种数学语句,它用“=”符号连接两个相等值的代数表达式。例如:在等式 3x+2 = 5 中,3x+ 2 是左侧表达式,5 是与“=”符号连接的右侧表达式。
主要有3种方程:
- 线性方程
- 二次方程
- 多项式方程
这里给出了两个由两个变量组成的方程,要找到数字,我们必须将这两个方程相加。
因为,一个方程包含正值,第二个方程包含正值和负值,通过将两个方程相加,一个变量被取消,我们得到另一个变量的值。
然后使用第二个变量的值,我们可以通过使用任何给定的方程来获取第一个变量的值。
因此,无法求解由两个变量组成的单个方程。
Just adding few points related to numbers:
- Sum of two odd numbers will always be even.
- Sum of two even numbers will always be even.
- Sum of one odd and one even number will always be odd.
两个数字的和是 19,它们的差是 5。找出这些数字。
解决方案:
Let the both numbers be first and second.
According to the problem statement:
first + second = 19 (Consider this as 1st equation)
first – second = 5 (Consider this as 2nd equation)
Add both equations:
first + second + first – second = 19 + 5
2 * first = 24
first = 24 / 2
first = 12
So from this we get first = 12, put this value in any equation i.e.
first + second = 19 (Put the value of first in this equation)
12+ second = 19
second = 19 – 12
second = 7
So, the numbers are 12 and 7.
If we consider the case i.e. second – first = 5, then the solution will be same and the first number will become 7 and second number will become 12.
类似问题
问题1:两个数之和是50,两个数之差是30。任务是找出这些数。
解决方案:
Let the both numbers be first and second.
According to the problem statement:
first + second = 50 (Consider this as 1st equation)
first – second = 30 (Consider this as 2nd equation)
Add both equations:
first + second + first – second = 50 + 30
2 * first = 80
first = 80 / 2
first = 40
So from this we get first = 40, put this value in any equation i.e.
first + second = 50 (Put the value of first in this equation)
40+ second = 50
second = 50 – 40
second = 10
So, the numbers are 40 and 10.
If we consider the case i.e. second – first = 30, then the solution will be same and the first number will become 10 and second number will become 40.
问题2:两个数之和是33,两个数之差是25。任务是找到这两个数。
解决方案:
Let both numbers be first and second.
According to the problem statement:
first + second = 33 (Consider this as 1st equation)
first – second = 25 (Consider this as 2nd equation)
Add both equations:
first + second + first – second = 33 + 25
2 * first = 58
first = 58 / 2
first = 29
So from this we get first = 29, put this value in any equation i.e.
first + second = 33 (Put the value of first in this equation)
29+ second = 33
second = 33 – 29
second = 4
So, the numbers are 29 and 4.
If we consider the case i.e. second – first = 25, then the solution will be same and the first number will become 4 and second number will become 29.