每日一题

Mathematics>Standard Multiple Choice

Read the following SAT test question and then click on a button to select your answer.

ax+5=4x-3
In the linear equation shown above, a is a constant. If the equation has no solution, what is the value of a?

A.1
B.2
C.3
D.4

答案和解析

答案：D

解析：

Choice D is correct. A linear equation in one variable will have no solution if the equation reduces to an equation of the form:

ax+b=cx+d,

where a=c and b≠d.

Therefore, if a=4, the equation 4x+5=4x-3 yields 5=-3. This is not true for any values of x and therefore this value of a results in an equation with no solutions.