4x+5y=7
y=3x+9
1) 4x+5(3x+9)=7 2) y=3(-2)+9
y= -6 +9
4x+15x+45=7 y=3
19x+45=7
19x= -38
x= -2
x is -2 and y is 3
Answer:
C
Step-by-step explanation:
A and B are wrong and with D they wouldn't be lines so imma go with C.
Sorry if it's wrong.
Answer:
A. 5x^2 − 2x − 24 = 0
Step-by-step explanation:
height = 5b-2
b =x
We can rewrite the height as
h = 5x-2
We know the formula for area of a triangle
A = 1/2 bh
A =1/2 x * (5x-2)
Distributing the x
A= 1/2 (5x^2 - 2x)
We know A =12
12 = 1/2 (5x^2 - 2x)
Multiply each side by 2
12*2 = 2*1/2 (5x^2 - 2x)
24 = 5x^2 - 2x
Subtract 24 from each side
24-24 = 5x^2 - 2x-24
0 = 5x^2 - 2x-24