9+10=19
proof, 9=1 plus 1 9 times (to lazy to write it out)
10=1 plus 1 10 times(to lazy)
so 1+1+1+1+1+1+1+1+1 + 1+1+1+1+1+1+1+1+1+<span>1 = 19</span>
Answer:

Step-by-step explanation:
Six times a number is decreased by fourteen, the result is 124.
Write an equation that represents this
(6 * x) - 14 = 124
Multiply 6 by x to remove the parenthesis
6x - 14 = 124
Add 14 to both sides of the equation
6x = 138
Divide both sides of the equation by 6
x = 23
The unknown number is 
Hope this helps :)
the two triangles are congruent
3:5:7:15
?:?:?:180
by using cross multiplication 3×180÷15=36
the measure of the smallest angle is 36°