Can someone please help me

1) Yes

Product of Means = Product of Extremes

4 × 21 = 7 × 12

84 = 84

2) No

Product of Means = Product of Extremes

2 × 2 = 3 × 3

4 ≠ 9

3) No

Cross multiplying

3 × 6 = 4 × 8

18 ≠ 32

4) Yes

Cross Multiplying

1 × 25 = 5 × 5

25 = 25

Step-by-step explanation:

1) 4 : 7   ? 12 : 21

If product of mean is equal to product of extremes, then they are proportion

Product of extremes = 4*21  = 84

Product of mean = 7 * 12 = 84

Product of extremes = Product of mean

They are in proportion

4 : 7 :: 12 : 21

2) 2 : 3 ? 3: 2

Product of extremes = 2*2 = 4

Product of mean = 3*3 = 9

Product of extremes ≠ Product of mean

They are not in proportion

2 : 3 ≠ 3 : 2

3) 3/4 ?  8/6

3 : 4 ?  8:6

Product of extremes = 3 * 6   = 18

Product of mean = 4 * 8 = 24

Product of extremes ≠ Product of mean

They are not in proportion

3 : 4 ≠ 8 : 6

4) 1/5  ? 5/25

1:5  ? 5 : 25

Product of extremes = 1 * 25 = 25

Product of mean = 5 * 5 = 25

Product of extremes = Product of mean

They are in proportion

1 : 5  :: 5 : 25

c

step-by-step explanation:

i think because what else can be a sample of every member

< xcy ≅ < xby

step-by-step explanation:

in δcax and δbax,

so, δcax ≅ δbax (side-angle-side or sas)

since δcax ≅ δbax, we can conclude < acx ≅ < abx

in δacy and δaby,

so, δacy ≅ δaby (side-angle-side or sas)

since δacy ≅ δaby, we can conclude < acy ≅ < aby

now,

< acy ≅ < aby

=> < acx + < xcy ≅ < abx + < xby

=> < acx + < xcy ≅ < acx + < xby   (since < acx ≅ < abx already proved above)

subtracting < acx from both sides, we get

< acx + < xcy -< acx ≅ < acx + < xby -< acx

cancelling out < acx and -< acx from both sides, we get

< xcy ≅ < xby (proved)