We can use linear combinations of the equations to eliminate variables.
3x - 4y = 1
-2x + 3y = 1
To eliminate y we'll make the linear combination of 3 times the first equation minus four times the second.
9x - 12y = 3
-8x + 12y = 4
Adding,
x = 7
We could solve for y directly but let's use another linear combination, twice the first plus three times the second:
2(3x - 4y) + 3(-2x + 3y)= 2(1)+3(1)
y = 5
Check: 3(7)-4(5)=1 good. -2(7)+3(5)=1 good.
Q18 Answer: (7,5)
y = -3x + 5
5x - 4y = -3
4y +1(5x - 4y) = 4(-3x + 5) + 1(-3)
5x = -12x + 20 -3
17 x = 17
x = 1
y = -3(1) + 5 = 2
Check: 5(1) - 4(2) = -3 good
Q19 Answer (1,2)
6x + 5y = 25
x = 2y + 24
6x = 12y + 144
5y = 25 - 12y - 144
17y = -119
y = -119/17= -7
x = 2y+24= 10
Check: 6(10)+5(-7)=25 good 2y+24=2(-7)+24=10=x good
Q20 Answer (10,-7)
3x + y = 18
-7x + 3y = -10
9x + 3y = 54
9x - -7x = 54 - -10
16x = 64
x=4
y = 18 -3x = 18-12=6
Check: 3(4)+6=18 good, -7(4)+3(6)=-10 good
Q21 Answer: (4,6)
Answer:
the area is the triangle is 37.5
Step-by-step explanation:
area = 1/2 base*height
Answer:
2 hours and 29 minutes
Step-by-step explanation:
if you change 9 hours to minutes you get 540 plus 17 equals 557. if you turn 6 hours to minutes it's 360 plus 48 equals 408. 557 minus 408 equals 149 minutes. Now if you convert it to hours and minutes you need to divide by 60. So if you divide it you get 2 hours and 29 minutes. hope this helped! :)
Answer:
triangle: 5x-8
square: 4x+8
Step-by-step explanation:
triangle: 2x + 2x + x -8
combine like terms
= 5x-8
square: x + 2 + x + 2 + x + 2 + x +2
combine like terms
= 4x + 8
Answer: 1,3,6
Explanation:
