求助一道数学题,谢谢

onemilenorths

 

Q34:

If Line k in the xy-plane has equation y = mx + b, where m and b are constants, what is the slope of k?

(1)     k is parallel to the line with equation y = (1-m)x + b +1.

(2)     k intersects the line with equation y = 2x + 3 at the point (2, 7).

                  

A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.

B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.

C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.

D. EACH statement ALONE is sufficient.

E. Statements (1) and (2) TOGETHER are NOT sufficient.

答案是A

请问两直线平行,斜率一定相等么?

还有条件2中的 k intersects 是什么意思呢?

谢谢解答

Sedulously

两直线平行,斜率一定相等

intersect是相交的意思啊，查查字典就知道了嘛

onemilenorths

thanks  a   lot !!!!!!!!!!!!!!