Area of triangle is
A=b•h/2
A=(10x+5)(2x-5)/2
A=20x^2-50x+10x-25/2
A=20x^2-40x-25/2
A=2(10x^2-20x-12.5)/2
cancel 2 in numerator and denominator
A=10x^2-20x-12.5 in^2
Hope this helps
1. 2x+8=3x+10
Step 1: Subtract 3x from both sides.
2x+8(-3x)= 3x+10 <span>(-3x)
</span>-x+8=10
Step 2: Subtract 8 from both sides.
-x+8 (-8) = 10 <span>(-8)
</span>-x=2
Step 3: Divide both sides by -1.
-x/(-1)=2/(-1)
x=-2
Answer= x=-2
2. -3x+9=2x-1
Step 1: Subtract 2x from each side.
-3x (-2x) +9= 2x-1 <span>(-2x)
</span>-5x+9=-1
Step 2: Subtract 9 from both sides.
-5x+9 (-9)=-1 (-9)
-5x=-10
Step 3: Divide -5 from both sides.
-5x/-5= -10/-5
x=2
The answer is 2.
3. 4x-7=5x-6
Step 1: Subtract 5x from both sides.
4x-7 (-5x)= 5x-6 (-5x)
-x-7=-6
Step 2: Add 7 to both sides.
-x-7 (+7)= -6 (+7)
-x=1
Step 3: Divide each side by -1.
-x/-1=1/-1
x=-1
The answer is -1.
They shouldn’t have to wait for each other because they are doing everything the same.
Both 3 miles away, both start at the same time, both at current rate
Answer: x=3 y=3
Step-by-step explanation:
Assuming you meant 2x+3y=15 as the first problem. You have to make either both the x’s or both the y’all equal in both equations first. Multiply the second equation by 2 (for x’s) and you’ll get 2x+2y=12. The 2x cancels out so you’re left with 3y=15 and 2y=12. Subtract 2y=12 from 3y=15 and you get y=3.
Repeat to figure out x. Multiple second equation by 3 (for equal y’s) and you get 3x+3y=18. This time the first equation is being subtracted from the second one. (3x+3y=18) - (2x+3y=15). Y’s cancel out and you’re left with (3x=18)-(2x=15. Subtract and you get x=3
