Answer:
Step-by-step explanation:
Actually Welcome to the Concept of the linear equations..
Here given value of x= 5 and y =1 , so we get as,
5a + b = 38 and 5b - a = 8
so, now we multiply equation no. 2 by 5 all over.
==> 25b - 5a = 40....(1)
hence adding new equation and equation no. 1
26b = 78
b = 78/26
hence b = 3 , and a = 7
If I’m getting this right the equation is: 0.00045 - 2.5 x 10 - 5? The dot in between 2.5 and 10 indicates a multiplication sign
So...
0.00045 - (2.5 x 10) - 5
0.00045 - 25 - 5
= -29.9999 -> -30