Answer:
x = -1 and x = 7
Step-by-step explanation:
2x^2 + 2x - 14x - 14
2x^2 - 12x -14
Divide through by 2 to simplify the expression
x^2 - 6x - 7
x^2 - 6x -7
Now, let's think of two numbers that when added up gives -6 and when multiplied gives -7
Yes! It's -7 and +1
-7 + 1 = -6 , and -7* 1 = -7
Now, lets substitute these numbers in the expression
x^2 -7x + x - 7
factorize
x(x - 7) + 1(x - 7)
(x + 1) (x - 7)
Now equate to zero
(x + 1) (x - 7) = 0
x + 1 = 0
subtract 1 from both sides
x +1 - 1 = 0 -1
x = -1
Also,
x - 7 = 0
Add 7 to both sides
x -7 + 7 = 0 + 7
x = 7
Hence, x = -1 and x =7
Answer:
x=0.8, y=2.2 (0.8, 2.2).
Step-by-step explanation:
y+x=3
y=1.5x+1
-------------
1.5x+1+x=3
2.5x=3-1
2.5x=2
x=2/2.5
x=0.8
y+0.8=3
y=3-0.8
y=2.2
Answer:
Let x = the number of marbles Tim has
Let 2x = the number of marbles Sue has
x + 2x + 15 = 63
3x = 48
x = 16 marbles
Step-by-step explanation:
Answer:
144.44 yards
Step-by-step explanation:
The formula to find circumference is: C = π · d
Since we already have most of the factors figured out, we just replace them with what we have.
C = 3.14 · 46 yrds
144.44 = 3.14 · 46
Answer:
Each shirt cost $<u>7</u> and each pair of shorts cost $<u>17</u> .
Step-by-step explanation:
let shirts be represented as x
let shorts be represented as y
Younger brother spent $79 on 4 new shirts and 3 pairs of shorts.
4 x + 3 y = $79 .......equation 1
Older brother purchased 7 new shirts and 8 pairs of shorts and paid a total of $185.
7 x + 8 y = $185 .......equation 2
multiply equation 1 by 7 and equation 2 by -4 and add both equations to get the value of y.
7 × (4 x + 3 y = $79) ⇒ +28 x + 21 y = $553
-4 × (7 x + 8 y = $185) ⇒ <u> -28 x - 32 y = - $740</u>
0 - 11 y = - $187 ⇒ -11 y = - $187
y = 
⇒ y = $17
shorts = y = $17
put value of y in equation 1
4 x + 3 ( $17 ) = $79 ⇒ 4x + $51 = $79 ⇒ 4x = $79 - $51
4x = $28 ⇒ x = 
⇒ x = $7
Shirts = x = $7
