Answer:
x=-2
y= 8
Step-by-step explanation:
Given data
10x – 2y = -36-----------1
7x – 2y = -30--------------2
-Subtract to eliminate y
3x-0= -6
3x= -6
x= -6/3
x= -2
Put x= -2 in
7(-2)– 2y = -30
-14-2y=-30
-14+30=2y
16=2y
y= 16/2
y= 8
Step-by-step explanation:
$20/hr carpenter pay
$25/hr blacksmith pay
Let c = hours working carpentry
Let b = hours working as blacksmith
c + b = 30 {equation 1}
20c + 25b = 690 {equation 2}
In equation 1 solve for one variable in terms of the other.
c = 30-b
Substitute that into equation 2:
20(30-b) + 25b = 690
600 - 20b + 25b = 690
5b = 90
b = 90/5
b = 18 hours working as a blacksmith
c = 30-b = 30-18 = 12 hours as a carpenter
An acute angle is any angle that is below 90 degrees, so 89 degrees is an ancute angle