I think it would be 13 hours possibly
<span>3x = y + 7
</span><span> y =3x-7
</span>
<span>8x = 2y + 5
</span><span>8x = 2(3x-7) + 5
8x=6x-14+5
8x-6x=-9
2x=-9
x=-4.5
</span><span>8x = 2y + 5
</span>8(4.5)=2y+5
36=2y+5
2y=31
y=15.5
Working out the expression 7(3ˣ) is first to calculate the value of 3ˣ then multiply the answer to 7.
For example, let x = 2
Then 7(3ˣ) = 7(3²) = 7 × 9 = 63
With the same value of x = 2, calculating 21ˣ = 21² = 441, which isn't the same answer with the expression 7(3ˣ)
Answer:
29
Step-by-step explanation:
6 + 3 x 9 - 4
6 + 27 - 4
33 - 4
=29
X=-1 and y=5
As when u replace the values x will give you negative 1 and when u replace negative 1 in y=-5x you get 5